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<SEC-DOCUMENT>0001292814-10-002246.txt : 20100701
<SEC-HEADER>0001292814-10-002246.hdr.sgml : 20100701
<ACCEPTANCE-DATETIME>20100630193913
ACCESSION NUMBER:		0001292814-10-002246
CONFORMED SUBMISSION TYPE:	NT 20-F
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20091231
FILED AS OF DATE:		20100701
DATE AS OF CHANGE:		20100630
EFFECTIVENESS DATE:		20100701

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			COMPANHIA DE SANEAMENTO BASICO DO ESTADO DE SAO PAULO-SABESP
		CENTRAL INDEX KEY:			0001170858
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER SUPPLY [4941]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			D5
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		NT 20-F
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31317
		FILM NUMBER:		10928514

	BUSINESS ADDRESS:	
		STREET 1:		RUA COSTA CARVALHO, 300
		STREET 2:		SAO PAULO
		CITY:			SP
		STATE:			D5
		ZIP:			05429-900
		BUSINESS PHONE:		011-55-11-3388-8000

	MAIL ADDRESS:	
		STREET 1:		RUA COSTA CARVALHO, 300
		STREET 2:		SAO PAULO
		CITY:			SP
		STATE:			D5
		ZIP:			05429-900
</SEC-HEADER>
<DOCUMENT>
<TYPE>NT 20-F
<SEQUENCE>1
<FILENAME>sbsform_12b25.htm
<DESCRIPTION>NOTIFICATION OF LATE FILING
<TEXT>

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<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION<BR>
WASHINGTON, D.C. 20549</FONT></B></P>
<P style="MARGIN: 6pt 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt; TEXT-TRANSFORM: uppercase" face="'Times New Roman Bold,serif'">FORM 12</FONT></B><B><FONT lang=EN-US style="FONT-SIZE: 12pt; TEXT-TRANSFORM: none" face="'Times New Roman Bold,serif'">b</FONT></B><B><FONT lang=EN-US style="FONT-SIZE: 12pt; TEXT-TRANSFORM: uppercase" face="'Times New Roman Bold,serif'">-25<BR>
<BR>
NOTIFICATION OF LATE FILING</FONT></B></P>
<P style="MARGIN: 6pt 0in 12pt; TEXT-ALIGN: right" align=right><FONT lang=EN-US style="FONT-WEIGHT: normal; FONT-SIZE: 12pt; TEXT-TRANSFORM: none" face="'Times New Roman,serif'">&nbsp;Commission File Number </FONT><U><FONT lang=EN-US style="FONT-WEIGHT: normal; FONT-SIZE: 12pt; TEXT-TRANSFORM: none" face="'Times New Roman,serif'">001&#8209;31317</FONT></U></P>
<P style="MARGIN: 6pt 0in 12pt; TEXT-ALIGN: right" align=right><FONT lang=EN-US style="FONT-WEIGHT: normal; FONT-SIZE: 12pt; TEXT-TRANSFORM: none" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 12pt; TEXT-INDENT: 0in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">(Check One):</FONT></I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> <BR>
</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form 10-K&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>x</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form 20-F&nbsp;&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form 11-K&nbsp;&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form 10-Q&nbsp;&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form 10-D&nbsp;&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form N-SAR&nbsp; </FONT><FONT lang=EN-US style="FONT-SI
ZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Form N-CSR</FONT></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0in"><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0in"><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">For Period Ended: </FONT><U><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; December 31, 2009&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Transition Report on Form 10-K&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Transition Report on Form 20-F&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Transition Report on Form 11-K<BR>
</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Transition Report on Form 10-Q<BR>
</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Transition Report on Form N-SAR</FONT></P>
<P style="MARGIN: 0in 0in 3pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0in"><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">For the Transition Period Ended:&nbsp;</FONT><U><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></I>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></I>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0in" align=center><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Read attached instruction sheet before preparing form.&nbsp; Please print or type.</FONT></I></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Nothing in this form shall be construed to imply that the Commission has verified any information contained herein.</FONT></B></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0.5in"><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">If the notification relates to a portion of the filing checked above, identify the items(s) to which<BR>
the notification relates: <BR>
<BR>
</FONT></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0in"><I><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'">N/A.</FONT></I></P>
<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"><BR>
<BR>
</FONT></B></P>
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<P style="MARGIN: 0in 0in 0pt" align=center><FONT style="mso-bidi-font-size: 10.0pt"><FONT lang=EN-US style="FONT-SIZE: 8pt" face="'Times New Roman,serif'">1</FONT></FONT></P>
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<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">PART I<BR>
REGISTRANT INFORMATION</FONT></B></P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=EN-US style="FONT-SIZE: 12pt; TEXT-DECORATION: none" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt"><U><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Companhia de Saneamento B&#225;sico do Estado de S&#227;o Paulo - SABESP&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Full Name of Registrant: &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></P>
<P style="MARGIN: 0in 0in 0pt; TEXT-INDENT: 0.5in"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></B></P>
<P style="MARGIN: 0in 0in 0pt"><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">N/A&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&n
bsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Former Name if Applicable:</FONT><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp; <BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></B></P>
<P style="MARGIN: 0in 0in 0pt"><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Rua Costa Carvalho, 300&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Address of Principal Executive Office (</FONT><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Street and Number</FONT></I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">):</FONT></P>
<P style="MARGIN: 0in 0in 0pt"><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">S&#227;o Paulo, SP, Brazil, 05429-900&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">City, State and Zip Code:</FONT></P>
<P style="MARGIN: 0in 0in 0pt 0.5in"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></B>&nbsp;</P>
<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">PART II<BR>
RULE 12b-25 (b) AND (c)</FONT></B></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">If the subject report could not be filed without unreasonable effort or expense and the registrant seeks relief pursuant to Rule 12b-25(b), the following should be completed.&nbsp; (Check box if appropriate.) </FONT></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 1in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
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<P style="MARGIN: 0in 0in 12pt 0.55in; TEXT-INDENT: -0.5in"><FONT style="FONT-SIZE: 11pt" face=Wingdings>&#254;</FONT><FONT style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> (a)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The reasons described in reasonable detail in Part III of this form could not&nbsp;&nbsp; be eliminated without unreasonable effort or expense;<BR>
<BR>
</FONT></P>
<P style="MARGIN: 0in 0in 12pt 0.55in; TEXT-INDENT: -0.5in"><FONT style="FONT-SIZE: 11pt" face=Wingdings>&#254;</FONT><FONT style="FONT-SIZE: 11pt" face="'Times New Roman,serif'"> </FONT><FONT style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">(b)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The subject annual report, semi-annual report, transition report on Form 10-K, 20-F, 11-K, Form N-SAR or Form N-CSR, or portion thereof, will be filed on or before the fifteenth calendar day following the prescribed due date; or the subject quarterly report or transition report on Form 10-Q or subject distribution report on Form 10-D, or portion thereof, will be filed on or before the fifth calendar day following the prescribed due date; and<BR>
<BR>
</FONT></P>
<P style="MARGIN: 0in 0in 12pt 0.55in; TEXT-INDENT: -0.5in"><FONT style="FONT-SIZE: 11pt" face=Wingdings>o</FONT><FONT style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> (c)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; The accountant&#146;s statement or other exhibit required by Rule 12b-25(c) has been attached if applicable.</FONT></P>
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<P style="MARGIN: 0in 0in 12pt; TEXT-ALIGN: center"><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">PART III<BR>
NARRATIVE</FONT></B></P>
<P style="MARGIN: 0in 0in 12pt; TEXT-INDENT: 0in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">State below in reasonable detail the reasons why Forms 10-K, 20-F, 11-K, 10-Q,10-D,&nbsp; N-SAR, N-CSR, or the transition report or portion thereof, could not be filed within the prescribed time period.</FONT></P>
<P style="MARGIN: 0in 0in 12pt; TEXT-INDENT: 0in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">The Registrant respectfully notifies the Securities and Exchange Commission that it was unable to complete its Annual Report on Form 20-F for fiscal year ended December 31, 2009 (the &#147;2009 Annual Report&#148;) in a timely manner without unreasonable effort or expense.&nbsp; The Registrant will file its first consolidated financial statements prepared under International Financial Reporting Standards (&#147;</FONT></I><I><FONT lang=EN-US style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line" face="'Times New Roman,serif'">IFRS&#148;), as issued by the International Accounting Standards Board, for the fiscal years ended December 31, 2009 and 2008.&nbsp; The Registrant&#146;s first-time preparation of Form 20-F using IFRS has proven to be more complex than expected.&nbsp; For this reason, the Registrant is unable to complete the consolidated financial statements and the necessary review pro
cedures to complete and file its Form 20-F within the prescribed time period without unreasonable effort and expense. </FONT></I></P>
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<P style="MARGIN: 0in 0in 12pt; TEXT-INDENT: 0in" align=center><B><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">PART IV<BR>
OTHER INFORMATION</FONT></B></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">(1)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Name and telephone number of person to contact in regard to this notification</FONT></P>
<P style="MARGIN: 0in 0in 0pt"><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Rui de Britto &#193;lvares Affonso&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT></U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; +55 11 3388 8247&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"><BR>
(Name)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (Area Code) (Telephone Number)<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT></P>
<P style="MARGIN: 0in 0in 12pt 0.5in; TEXT-INDENT: -0.5in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">(2) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Have all other periodic reports required under Section 13 or 15(d) of the Securities Exchange Act of 1934 or Section 30 of the Investment Company Act of 1940 during the preceding 12 months or for such shorter period that the registrant was required to file such report(s) been filed?&nbsp; If the answer is no, identify report(s).</FONT></P>
<P style="MARGIN: 0in 0in 3pt; TEXT-INDENT: 0.5in; TEXT-ALIGN: left" align=left><FONT lang=EN-US style="FONT-SIZE: 11pt" face=Wingdings>&#254;</FONT><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'"> Yes&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 11pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 11pt" face="'Times New Roman,serif'"> No</FONT></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 12pt 0.5in; TEXT-INDENT: -0.5in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">(3) &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Is it anticipated that any significant change in results of operations from the corresponding period for the last fiscal year will be reflected by the earnings statements to be included in the subject report or portion thereof?</FONT></P>
<P style="MARGIN: 12pt 0in 12pt 0.5in"><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>&#254;</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> Yes&nbsp; </FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face=Wingdings>o</FONT><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"> No </FONT></P>
<P style="MARGIN: 12pt 0in 12pt 0.5in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">If so, attach an explanation of the anticipated change, both narratively and quantitatively, and, if appropriate, state the reasons why a reasonable estimate of the results cannot be made.</FONT></I></P>
<P style="MARGIN: 12pt 0in 12pt 0.5in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">As the Registrant is adopting IFRS for the first time for the years ended December 31, 2009 and 2008, it is in the process of finalizing all required adjustments from Brazilian GAAP to IFRS and is unable</FONT></I><I><FONT lang=EN-US style="FONT-SIZE: 12pt; LAYOUT-GRID-MODE: line" face="'Times New Roman,serif'"> to anticipate any significant change in results of operations from the corresponding period for the last fiscal year under IFRS without unreasonable effort and expense.</FONT></I></P>
<P style="MARGIN: 12pt 0in 12pt 0.5in"><I><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT></I>&nbsp;</P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">____________</FONT><U><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Companhia de Saneamento B&#225;sico do Estado de S&#227;o Paulo &#150; SABESP&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT></U><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"><BR>
</FONT><I><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; (Name of Registrant as Specified in Charter)</FONT></I></P>
<P style="MARGIN: 0in 0in 0pt"><FONT lang=PT-BR style="FONT-SIZE: 12pt" face="'Times New Roman,serif'"></FONT>&nbsp;</P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">has caused this notification to be signed on its behalf by the undersigned thereunto duly authorized.</FONT></P>
<P style="MARGIN: 0in 0in 12pt"><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">Date:&nbsp;&nbsp; July 1, 2010&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<BR>
<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;By:&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </FONT><U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">/s/&nbsp;&nbsp;Rui de Britto &#193;lvares Affonso&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<BR>
</FONT></U><FONT lang=EN-US style="FONT-SIZE: 12pt" face="'Times New Roman,serif'">&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Name: Rui de Britto &#193;lvares Affonso<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Title:&nbsp;&nbsp; Chief Financial Officer and Investor<BR>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Relations Officer</FONT></P>
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