<SEC-DOCUMENT>0000824142-14-000030.txt : 20140327
<SEC-HEADER>0000824142-14-000030.hdr.sgml : 20140327
<ACCEPTANCE-DATETIME>20140327143515
ACCESSION NUMBER:		0000824142-14-000030
CONFORMED SUBMISSION TYPE:	10-K/A
PUBLIC DOCUMENT COUNT:		5
CONFORMED PERIOD OF REPORT:	20131231
FILED AS OF DATE:		20140327
DATE AS OF CHANGE:		20140327

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			AAON INC
		CENTRAL INDEX KEY:			0000824142
		STANDARD INDUSTRIAL CLASSIFICATION:	AIR COND & WARM AIR HEATING EQUIP & COMM & INDL REFRIG EQUIP [3585]
		IRS NUMBER:				870448736
		STATE OF INCORPORATION:			NV
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		10-K/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-18953
		FILM NUMBER:		14721234

	BUSINESS ADDRESS:	
		STREET 1:		2425 SOUTH YUKON
		CITY:			TULSA
		STATE:			OK
		ZIP:			74107
		BUSINESS PHONE:		9185832266

	MAIL ADDRESS:	
		STREET 1:		2425 SOUTH YUKON
		CITY:			TULSA
		STATE:			OK
		ZIP:			74107

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	DIAMOND HEAD RESOURCES INC
		DATE OF NAME CHANGE:	19900808
</SEC-HEADER>
<DOCUMENT>
<TYPE>10-K/A
<SEQUENCE>1
<FILENAME>aaon_10ka123113amendment1.htm
<DESCRIPTION>10-K/A
<TEXT>
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<a name="sb12528ac06c446e583476f4580b67602"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">UNITED STATES</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">SECURITIES AND EXCHANGE COMMISSION</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Washington, D.C. 20549</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">FORM 10-K/A</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">(Amendment No. 1)</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="2"></td></tr><tr><td width="5%"></td><td width="95%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">[X]</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934</font></div></td></tr></table></div></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">For the fiscal year ended December 31, 2013 </font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">or</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="2"></td></tr><tr><td width="5%"></td><td width="95%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:Arial;font-size:10pt;font-weight:bold;">[</font><font style="font-family:Arial;font-size:10pt;font-weight:bold;">&#160;</font><font style="font-family:Arial;font-size:10pt;font-weight:bold;">]</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934</font></div></td></tr></table></div></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">For the transition period from _____________________________ to _____________________________</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Commission file number: 0-18953</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">AAON, INC.</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(Exact name of registrant as specified in its charter)</font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:91.40625%;border-collapse:collapse;text-align:left;"><tr><td colspan="2"></td></tr><tr><td width="50%"></td><td width="50%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Nevada</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">87-0448736</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(State or other jurisdiction</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(IRS Employer</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">of incorporation or organization)</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Identification No.)</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:26px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:26px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">2425 South Yukon, Tulsa, Oklahoma</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">74107</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(Address of principal executive offices)</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(Zip Code)</font></div></td></tr></table></div></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Registrant's telephone number, including area code: (918) 583-2266</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Securities registered pursuant to Section 12(b) of the Act: None</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Securities registered pursuant to Section 12(g) of the Act:</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Common Stock, par value $.004</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(Title of Class)</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">Rights to Purchase Series A Preferred Stock</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(Title of Class)</font></div><div style="line-height:174%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. </font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[</font><font style="font-family:inherit;font-size:10pt;">&#32;</font><font style="font-family:inherit;font-size:10pt;">] Yes [X] No</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. </font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[</font><font style="font-family:inherit;font-size:10pt;">&#32;</font><font style="font-family:inherit;font-size:10pt;">] Yes [X] No</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb12528ac06c446e583476f4580b67602"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.</font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[X] Yes [</font><font style="font-family:inherit;font-size:10pt;">&#32;</font><font style="font-family:inherit;font-size:10pt;">] No</font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).</font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[X] Yes [ ] No</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.</font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[  ]</font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company (as defined in Rule 12b-2 of the Securities Exchange Act of 1934).</font></div><div style="line-height:174%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:Arial;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:91.40625%;border-collapse:collapse;text-align:left;"><tr><td colspan="2"></td></tr><tr><td width="50%"></td><td width="50%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Large accelerated filer [</font><font style="font-family:inherit;font-size:10pt;">&#160;</font><font style="font-family:inherit;font-size:10pt;">]</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Accelerated filer [</font><font style="font-family:inherit;font-size:10pt;text-decoration:underline;">X</font><font style="font-family:inherit;font-size:10pt;">]</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Non-accelerated filer [</font><font style="font-family:inherit;font-size:10pt;">&#160;</font><font style="font-family:inherit;font-size:10pt;">]</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Smaller reporting company [</font><font style="font-family:inherit;font-size:10pt;">&#160;</font><font style="font-family:inherit;font-size:10pt;">]</font></div></td></tr></table></div></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Indicate by check mark whether the registrant is a shell company (as defined by Rule 12b-2 of the Act.) </font></div><div style="line-height:174%;text-align:right;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">[</font><font style="font-family:inherit;font-size:10pt;">&#32;</font><font style="font-family:inherit;font-size:10pt;">] Yes [X] No</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The aggregate market value of the common equity held by non-affiliates computed by reference to the closing price of registrant&#8217;s common stock on the last business day of registrant&#8217;s most recently completed second quarter June 30, 2013 was $617.3 million.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">As of March 1, 2014, registrant had outstanding a total of 36,687,591</font><font style="font-family:inherit;font-size:10pt;font-weight:bold;">&#32;</font><font style="font-family:inherit;font-size:10pt;">shares of its $.004 par value Common Stock.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">DOCUMENTS INCORPORATED BY REFERENCE</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Portions of registrant's definitive Proxy Statement to be filed in connection with the Annual Meeting of Stockholders to be held May 20, 2014, are incorporated into Part III of this report.</font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Explanatory Note</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">AAON, Inc., a Nevada corporation (together with its subsidiaries, &#8220;AAON&#8221;, &#8220;we&#8221;, &#8220;us&#8221;, &#8220;our&#8221; or the &#8220;Company&#8221;), is filing this Amendment No. 1 on Form 10-K/A (this &#8220;Amendment&#8221;) to our Annual Report on Form 10-K for the year ended December 31, 2013, as filed with the U.S. Securities and Exchange Commission (the "SEC") on March 13, 2014, (the "Original Filing").  The sole purpose of this Amendment is to correct the following errors:</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:48px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">1)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Uncheck on the cover page the section that states &#8220;Indicate by check mark if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K is not contained herein, and will not be contained, to the best of registrant's knowledge, in definitive proxy or information statements incorporated by reference in Part III of this Form 10-K or any amendment to this Form 10-K.&#8221; as the definitive proxy statement incorporated by reference in Part III of the Original Filing will include disclosure of delinquent filers.</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:48px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">2)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Update the Representatives section in Part I, Item 1 of the Original Filing to state that we utilize approximately 82 independent manufacturer representatives&#8217; organizations having 113 offices.</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:48px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">3)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Update the Employees section in Part I, Item 1 of the Original Filing to state that as of March 1, 2014, we employed 1,431 permanent employees.</font></div></td></tr></table><div style="line-height:174%;text-align:justify;padding-left:24px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">As required by Rule 12b-15 promulgated under the Securities Exchange Act of 1934, as amended, new certifications by the Company&#8217;s principal executive officer and principal financial officer are filed as exhibits to this Amendment.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Except as set forth herein, this Amendment does not amend or otherwise update any other information in the Original Filing and does not reflect events occurring after the filing of the Original Filing.  Accordingly, this Amendment should be read in conjunction with the Original Filing and our other filings made with the SEC on or after March 13, 2014. </font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">PART I</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Item 1. Business.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">General Development and Description of Business</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">AAON, Inc., a Nevada corporation, ("AAON Nevada") was incorporated on August 18, 1987. We have two operating subsidiaries, AAON, Inc., an Oklahoma corporation, and AAON Coil Products, Inc., a Texas corporation. Unless the context otherwise requires, references in this Annual Report to &#8220;AAON,&#8221; the &#8220;Company&#8221;, &#8220;we&#8221;, &#8220;us&#8221;, &#8220;our&#8221;, or &#8220;ours&#8221; refer to AAON Nevada and our subsidiaries.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We are engaged in the manufacture and sale of air-conditioning and heating equipment. Our products consist of rooftop units, chillers, air-handling units, make-up air units, heat recovery units, condensing units, commercial-self contained units and coils.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Products and Markets</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our products serve the commercial and industrial new construction and replacement markets. To date, our sales have been primarily to the domestic market. Foreign sales accounted for approximately $17.5 million, $16.2 million and $13.6 million of our sales in 2013, 2012 and 2011, respectively.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our rooftop and condensing unit markets primarily consist of units installed on commercial or industrial structures of generally less than ten stories in height. Our air handling units, self-contained units, chillers, outdoor mechanical rooms and coils are applicable to all sizes of commercial and industrial buildings.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The size of these markets is determined primarily by the number of commercial and industrial building completions. The replacement market consists of products installed to replace existing units/components that are worn or damaged. Currently, slightly over half of the industry's market consists of replacement units.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The commercial and industrial new construction market is subject to cyclical fluctuations in that it is generally tied to housing starts, but has a lag factor of six to 18 months. Housing starts, in turn, are affected by such factors as interest rates, the state of the economy, population growth and the relative age of the population. When new construction is down, we emphasize the replacement market.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Based on our 2013 level of sales of $321.1 million, we estimate that we have approximately a 15% share of the rooftop market and a 1-3% share of other markets. Approximately 55% of our sales were generated from the renovation and replacement markets and 45% from new construction. The percentage of sales for new construction vs. replacement to particular customers is related to the customer&#8217;s stage of development.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We purchase certain components, fabricate sheet metal and tubing and then assemble and test the finished products. Our primary finished products consist of a single unit system containing heating and cooling in a self-contained cabinet, referred to in the industry as "unitary products&#8221;. Our other finished products are chillers, outdoor mechanical rooms, coils, air handling units, condensing units, makeup air units, energy recovery units and self-contained units. </font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We offer three groups of rooftop units: the RQ Series, consisting of five cooling sizes ranging from two to six tons; the RN Series, offered in 27 cooling sizes ranging from six to 140 tons; and the RL Series, which is offered in 21 cooling sizes ranging from 40 to 240 tons. </font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We also offer the SA and SB Series as indoor packaged, water-cooled or water-source heat pump units with cooling capacities of three to 70 tons.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We manufacture a LC Series chiller, air-cooled, a LN Series chiller, air-cooled, and a LL Series chiller and packaged outdoor mechanical room, which are available in both air-cooled condensing and evaporative-cooled configurations, covering a range of three to 540 tons. BL Series boiler outdoor mechanical rooms are also available with 500-6,000 MBH heating capacity.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We offer four groups of condensing units: the CB Series, two to five tons; the CC Series, two to 63 tons; the CN Series, 55 to 140 tons; and the CL Series, 45 to 230 tons.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our air-handling units consist of the indoor F1 Series and H3/V3 Series and the modular M2 and M3 Series, as well as air handling unit versions of the RQ, RN, RL and SA Series units. </font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our energy recovery option applicable to our RQ, RN and RL units, as well as our M2 and M3 Series air handling units, respond to the U.S. Clean Air Act mandate to increase fresh air in commercial structures. Our products are designed to compete on the higher quality end of standardized products.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Performance characteristics of our products range in cooling capacity from two to 540 tons and in heating capacity from 69,000 to 9,000,000 BTUs. All of our products meet the Department of Energy's (&#8220;DOE&#8221;) minimum efficiency standards, which define the maximum amount of energy to be used in producing a given amount of cooling. Many of our units far exceed these minimum standards and are among the highest efficiency units currently available.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">A typical commercial building installation requires a ton of air-conditioning for every 300-400 square feet or, for a 100,000 square foot building, 250 tons of air-conditioning, which can involve multiple units. </font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Major Customers</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">No customer accounted for 10% or more of our sales during 2013, 2012 or 2011.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Sources and Availability of Raw Materials</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The most important materials we purchase are steel, copper and aluminum, which are obtained from domestic suppliers. We also purchase from other domestic manufacturers certain components, including compressors, electric motors and electrical controls used in our products. We attempt to obtain the lowest possible cost in our purchases of raw materials and components, consistent with meeting specified quality standards. We are not dependent upon any one source for raw materials or the major components of our manufactured products. By having multiple suppliers, we believe that we will have adequate sources of supplies to meet our manufacturing requirements for the foreseeable future.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Sourcing of raw materials may be impacted in the future by the Dodd-Frank Wall Street Reform and Consumer Protection Act (the "Dodd-Frank Act") that contains provisions to improve transparency and accountability concerning the supply of certain minerals, known as "conflict minerals", originating from the Democratic Republic of Congo and adjoining countries. As companies begin implementing the requirements adopted by the Securities and Exchange Commission ("SEC") in response to the provisions in the Dodd-Frank Act, availability of materials that contain conflict minerals may be affected. </font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We attempt to limit the impact of price fluctuations on these materials by entering into cancelable and non-cancelable fixed price contracts with our major suppliers for periods of six to 18 months. We expect to receive delivery of raw materials from our fixed price contracts for use in our manufacturing operations.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Representatives</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We employ a sales staff of 20 individuals and utilize approximately 82 independent manufacturer representatives' organizations (&#8220;Representatives&#8221;) having 113 offices to market our products in the United States and Canada. We also have one international sales organization, which utilizes 12 distributors in other countries. Sales are made directly to the contractor or end user, with shipments being made from our Tulsa, Oklahoma, and Longview, Texas, plants to the job site.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our products and sales strategy focuses on niche markets. The targeted markets for our equipment are customers seeking products of better quality than offered, and/or options not offered, by standardized manufacturers.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">To support and service our customers and the ultimate consumer, we provide parts availability through our sales offices. We also have factory service organizations at each of our plants. Additionally, a number of the Representatives we utilize have their own service organizations, which, in connection with us, provide the necessary warranty work and/or normal service to customers.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Warranties</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our product warranty policy is: the earlier of one year from the date of first use or 18 months from date of shipment for parts only; an additional four years for compressors (if applicable); 15 years on aluminized steel gas-fired heat exchangers (if applicable); 25 years on stainless steel heat exchangers (if applicable); and ten years on gas-fired heat exchangers in RL products (if applicable). Our warranty policy for the RQ series covers parts for two years from date of unit shipment and labor for one year from date of unit shipment.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The Company also sells extended warranties on parts for various lengths of time ranging from six months to ten years. Revenue for these separately priced warranties is deferred and recognized on a straight-line basis over the separately priced warranty period.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Research and Development</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our products are engineered for performance, flexibility and serviceability. This has become a critical factor in competing in the heating, ventilation and air conditioning (&#8220;HVAC&#8221;) equipment industry. We must continually develop new and improved products in order to compete effectively and to meet evolving regulatory standards in all of our major product lines.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">All of our Research and Development ("R&amp;D") activities are self-sponsored, rather than customer-sponsored. R&amp;D has involved the RQ, RN and RL (rooftop units), F1, H/V, M2 and M3 (air handlers), LC and LL (chillers), CB and CC (condensing units), SA (commercial self-contained units) and BL (boilers), as well as component evaluation and refinement, development of control systems and new product development. We incurred research and development expenses of approximately $5.2 million, $3.6 million, and $4.8 million in 2013, 2012 and 2011, respectively.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Backlog</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our backlog as of March 1, 2014 was approximately $48.8 million compared to approximately $51.1 million as of March 1, 2013. The current backlog consists of orders considered by management to be firm and generally are filled on average within approximately 60 to 90 days after an order is deemed to become firm; however, the orders are subject to cancellation by the customers.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Working Capital Practices</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Working capital practices in the industry center on inventories and accounts receivable. Our management regularly reviews our working capital with a view of maintaining the lowest level consistent with requirements of anticipated levels of operation. Our greatest needs arise during the months of July - November, the peak season for inventory (primarily purchased material) and accounts receivable. Our working capital requirements are generally met by cash flow from operations and a bank revolving credit facility, which currently permits borrowings up to $30 million and had a zero balance at December 31, 2013. We believe that we will have sufficient funds available to meet our working capital needs for the foreseeable future.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Seasonality</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Sales of our products are moderately seasonal with the peak period being July - November of each year due to timing of construction projects being directly related to warmer weather.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Competition</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In the standardized market, we compete primarily with Lennox International, Inc., Trane (Ingersoll Rand Limited), York (Johnson Controls Inc.) and Carrier (United Technologies Corporation). All of these competitors are substantially larger and have greater resources than we do. Our products compete on the basis of total value, quality, function, serviceability, efficiency, availability of product, product line recognition and acceptability of sales outlet. However, in new construction where the contractor is the purchasing decision maker, we are often at a competitive disadvantage because of the emphasis placed on initial cost. In the replacement market and other owner-controlled purchases, we have a better chance of getting the business since quality and long-term cost are generally taken into account.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Employees</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">As of March 1, 2014, we employed 1,431 permanent employees. Our employees are not represented by unions. Management considers its relations with our employees to be good.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Patents, Trademarks, Licenses and Concessions</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">We do not consider any patents, trademarks, licenses or concessions to be material to our business operations, other than patents issued regarding our heat recovery wheel option, blower, gas-fired heat exchanger and evaporative condenser desuperheater which have terms of twenty years with expiration dates ranging from 2016 to 2022. </font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sb1e5cc710ee941629b4cbd146f05e9d9"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Environmental Matters</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Laws concerning the environment that affect or could affect our operations include, among others, the Clean Water Act, the Clean Air Act, the Resource Conservation and Recovery Act, the Occupational Safety and Health Act, the National Environmental Policy Act, the Toxic Substances Control Act, regulations promulgated under these Acts, and any other federal, state or local laws or regulations governing environmental matters. We believe that we are in compliance with these laws and that future compliance will not materially affect our earnings or competitive position.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Available Information</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Our Internet website address is http://www.aaon.com. Our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended, will be available free of charge through our Internet website as soon as reasonably practicable after we electronically file such material with, or furnish it to, the SEC. The information on our website is not a part of, or incorporated by reference into, this annual report on Form 10-K.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Copies of any materials we file with the SEC can also be obtained free of charge through the SEC&#8217;s website at http://www.sec.gov, at the SEC&#8217;s Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549, or by calling the SEC at 1-800-732-0330. </font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="sff05a5c3e25a49b2a112877754cc3cc3"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">PART IV</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Item 15. 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style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:20px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;text-decoration:underline;">Exhibit Number</font></div></td><td colspan="4" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;font-weight:bold;text-decoration:underline;">Exhibit Description</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:8pt;"><font 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style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:right;font-size:8pt;"><font style="font-family:inherit;font-size:8pt;">+ Filed herewith</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr></table></div></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:Arial;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:Arial;font-size:10pt;"><br></font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="s413b6a364c7e4eddaee2e464346b59ac"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:120%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">SIGNATURES</font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Pursuant to the requirement of Section 13 or 15(d) of the Securities Exchange Act of 1934, as amended, the Registrant has duly caused this report to be signed on its behalf by the undersigned, hereunto duly authorized.</font></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;&#160;</font></div><div style="line-height:120%;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;width:99.609375%;border-collapse:collapse;text-align:left;"><tr><td colspan="4"></td></tr><tr><td width="7%"></td><td width="47%"></td><td width="5%"></td><td width="41%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td colspan="2" style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">AAON, INC.</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Dated:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">March 27, 2014</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">By:&#160;</font></div></td><td style="vertical-align:bottom;border-bottom:2px solid #000000;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">/s/ Norman H. Asbjornson&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Norman H. Asbjornson, President</font></div></td></tr></table></div></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</body>
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<TYPE>EX-31.1
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<FILENAME>aaon_10ka123113exhibit311.htm
<DESCRIPTION>EXHIBIT
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<a name="s3324d0b04e6546a19ef305a21e4e6e69"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:right;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Exhibit 31.1</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">&#160;</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">CERTIFICATION</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">I, Norman H. Asbjornson, certify that:</font></div><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">1.</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">I have reviewed this Annual Report on Form 10-K of AAON, Inc., as amended by the Form 10-K/A filed March 27, 2014;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">2.</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">3.</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">4.</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The registrant&#8217;s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">a)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including our consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">b)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">c)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">evaluated the effectiveness of the registrant&#8217;s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">d)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">disclosed in this report any change in the registrant&#8217;s internal controls over financial reporting that occurred during the registrant&#8217;s most recent fiscal quarter (the registrant&#8217;s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant&#8217;s internal control over financial reporting; and</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">5.</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The registrant&#8217;s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant&#8217;s auditors and the audit committee of registrant&#8217;s board of directors (or persons performing the equivalent functions):</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">a)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant&#8217;s ability to record, process, summarize and report financial information; and</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">b)</font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant&#8217;s internal control over financial reporting.</font></div></td></tr></table><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="s3324d0b04e6546a19ef305a21e4e6e69"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td width="6%"></td><td width="52%"></td><td width="42%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Dated:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">March&#160;27, 2014</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">/s/ Norman H. Asbjornson</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Norman H. Asbjornson</font></div><div style="padding-bottom:1px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Chief Executive Officer</font></div></td></tr></table></div></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</body>
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<TYPE>EX-31.2
<SEQUENCE>3
<FILENAME>aaon_10ka123113exhibit312.htm
<DESCRIPTION>EXHIBIT
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<a name="saba87b1ba2ac4683bacaf59f789914f4"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:right;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Exhibit 31.2</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">CERTIFICATION</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">I, Scott M. Asbjornson, certify that:</font></div><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">1.</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">I have reviewed this Annual Report on Form 10-K of AAON, Inc., as amended by the Form 10-K/A filed on March 27, 2014;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">2.</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a material fact necessary to make the statements made, in light of the circumstances under which such statements were made, not misleading with respect to the period covered by this report;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">3.</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Based on my knowledge, the financial statements, and other financial information included in this report, fairly present in all material respects the financial condition, results of operations and cash flows of the registrant as of, and for, the periods presented in this report;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">4.</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The registrant&#8217;s other certifying officer and I are responsible for establishing and maintaining disclosure controls and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e) and internal control over financial reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f)) for the registrant and have:</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">a)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">designed such disclosure controls and procedures, or caused such disclosure controls and procedures to be designed under our supervision, to ensure that material information relating to the registrant, including our consolidated subsidiaries, is made known to us by others within those entities, particularly during the period in which this report is being prepared;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">b)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">designed such internal control over financial reporting, or caused such internal control over financial reporting to be designed under our supervision, to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">c)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">evaluated the effectiveness of the registrant&#8217;s disclosure controls and procedures and presented in this report our conclusions about the effectiveness of the disclosure controls and procedures, as of the end of the period covered by this report based on such evaluation;</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">d)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">disclosed in this report any change in the registrant&#8217;s internal controls over financial reporting that occurred during the registrant&#8217;s most recent fiscal quarter (the registrant&#8217;s fourth fiscal quarter in the case of an annual report) that has materially affected, or is reasonably likely to materially affect, the registrant&#8217;s internal control over financial reporting; and</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:60px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:24px;"><font style="font-family:inherit;font-size:10pt;">5.</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">The registrant&#8217;s other certifying officer and I have disclosed, based on our most recent evaluation of internal control over financial reporting, to the registrant&#8217;s auditors and the audit committee of registrant&#8217;s board of directors (or persons performing the equivalent functions):</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">a)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">all significant deficiencies and material weaknesses in the design or operation of internal control over financial reporting which are reasonably likely to adversely affect the registrant&#8217;s ability to record, process, summarize and report financial information; and</font></div></td></tr></table><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman; font-size:10pt;"><tr><td style="width:96px;"></td><td></td></tr><tr><td style="vertical-align:top"><div style="line-height:174%;font-size:10pt;padding-left:60px;"><font style="font-family:inherit;font-size:10pt;">b)</font><font style="font-family:inherit;font-size:10pt;"></font></div></td><td style="vertical-align:top;"><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">any fraud, whether or not material, that involves management or other employees who have a significant role in the registrant&#8217;s internal control over financial reporting.</font></div></td></tr></table><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><hr style="page-break-after:always"><a name="saba87b1ba2ac4683bacaf59f789914f4"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td width="6%"></td><td width="52%"></td><td width="42%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Dated:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">March&#160;27, 2014</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">/s/ Scott M. Asbjornson</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Scott M. Asbjornson</font></div><div style="padding-bottom:1px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Chief Financial Officer</font></div></td></tr></table></div></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</body>
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</DOCUMENT>
<DOCUMENT>
<TYPE>EX-32.1
<SEQUENCE>4
<FILENAME>aaon_10ka123113exhibit321.htm
<DESCRIPTION>EXHIBIT
<TEXT>
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<a name="s3b0288d097e6492189fc1e73b47f8be2"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:right;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Exhibit 32.1</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">CERTIFICATION PURSUANT TO</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">18 U.S.C. SECTION 1350,</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">AS ADOPTED PURSUANT TO</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In connection with the Annual Report of AAON, Inc. (the &#8220;Company&#8221;), on Form 10-K for the year ended December 31, 2013, as filed with the Securities and Exchange Commission on the date hereof (the &#8220;Report&#8221;) together with Form 10-K/A filed on March 27, 2014 amending such Report, I, Norman H. Asbjornson, Chief Executive Officer of the Company, certify, pursuant to 18 U.S.C. &#167; 1350, as adopted pursuant to &#167; 906 of the Sarbanes-Oxley Act of 2002, that:</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;padding-left:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(1)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;padding-left:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(2)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;The information contained in the Report fairly presents, in all material respects, the financial condition and our results of operations.</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td width="6%"></td><td width="52%"></td><td width="42%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Dated:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">March&#160;27, 2014</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">/s/ Norman H. Asbjornson</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Norman H. Asbjornson</font></div><div style="padding-bottom:1px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Chief Executive Officer</font></div></td></tr></table></div></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</body>
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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-32.2
<SEQUENCE>5
<FILENAME>aaon_10ka123113exhibit322.htm
<DESCRIPTION>EXHIBIT
<TEXT>
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<a name="sd72d6a3537294c8ca1508f014c5baabe"></a><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div><br><div style="line-height:174%;text-align:right;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">Exhibit 32.2</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">CERTIFICATION PURSUANT TO</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">18 U.S.C. SECTION 1350,</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">AS ADOPTED PURSUANT TO</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;font-weight:bold;">SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002</font></div><div style="line-height:174%;text-align:center;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;text-indent:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">In connection with the Annual Report of AAON, Inc. (the &#8220;Company&#8221;), on Form 10-K for the year ended December 31, 2013, as filed with the Securities and Exchange Commission on the date hereof (the &#8220;Report&#8221;) together with Form 10-K/A filed on March 27, 2014 amending such Report, I, Scott M. Asbjornson, Chief Financial Officer of the Company, certify, pursuant to 18 U.S.C. &#167; 1350, as adopted pursuant to &#167; 906 of the Sarbanes-Oxley Act of 2002, that:</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;padding-left:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(1)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;The Report fully complies with the requirements of section 13(a) or 15(d) of the Securities Exchange Act of 1934; and</font></div><div style="line-height:174%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:174%;text-align:justify;padding-left:48px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">(2)&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160;The information contained in the Report fairly presents, in all material respects, the financial condition and our results of operations.</font></div><div style="line-height:174%;text-align:justify;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><div style="line-height:120%;text-align:center;font-size:10pt;"><div style="padding-left:0px;text-indent:0px;line-height:normal;padding-top:10px;"><table cellpadding="0" cellspacing="0" style="font-family:Times New Roman;font-size:10pt;margin-left:auto;margin-right:auto;width:100%;border-collapse:collapse;text-align:left;"><tr><td colspan="3"></td></tr><tr><td width="6%"></td><td width="52%"></td><td width="42%"></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Dated:</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">March&#160;27, 2014</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="text-align:left;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">/s/ Scott M. Asbjornson</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;height:5px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td></tr><tr><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="overflow:hidden;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">&#160;</font></div></td><td style="vertical-align:bottom;padding-left:2px;padding-top:2px;padding-bottom:2px;padding-right:2px;"><div style="font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Scott M. Asbjornson</font></div><div style="padding-bottom:1px;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;">Chief Financial Officer</font></div></td></tr></table></div></div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div><br><div><div style="line-height:120%;font-size:10pt;"><font style="font-family:inherit;font-size:10pt;"><br></font></div></div>	</body>
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</SEC-DOCUMENT>
