<SEC-DOCUMENT>0000950123-18-006159.txt : 20180822
<SEC-HEADER>0000950123-18-006159.hdr.sgml : 20180822
<ACCEPTANCE-DATETIME>20180606171857
<PRIVATE-TO-PUBLIC>
ACCESSION NUMBER:		0000950123-18-006159
CONFORMED SUBMISSION TYPE:	DRSLTR
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20180606

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Tenable Holdings, Inc.
		CENTRAL INDEX KEY:			0001660280
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		IRS NUMBER:				475580846
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		DRSLTR

	BUSINESS ADDRESS:	
		STREET 1:		7021 COLUMBIA GATEWAY DRIVE, SUITE 500
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
		BUSINESS PHONE:		410-872-0555

	MAIL ADDRESS:	
		STREET 1:		7021 COLUMBIA GATEWAY DRIVE, SUITE 500
		CITY:			COLUMBIA
		STATE:			MD
		ZIP:			21046
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<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Eric C. Jensen</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">+1 650 843 5049</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:10pt; font-family:Times New Roman">ejensen@cooley.com</P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top" ALIGN="right">VIA EDGAR</TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">June&nbsp;6, 2018 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">U.S.
Securities and Exchange Commission </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Division of Corporation Finance </P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">100 F Street, N.E. </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Washington, DC 20549 </P>
<P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">Attn:</TD>
<TD ALIGN="left" VALIGN="top">Barbara C. Jacobs, Assistant Director </TD></TR></TABLE>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Jeff Kauten, Attorney-Advisor </TD></TR></TABLE>
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<TD ALIGN="left" VALIGN="top">Christine Dietz, Assistant Chief Accountant </TD></TR></TABLE>
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<TD ALIGN="left" VALIGN="top">Joyce Sweeney, Staff Accountant </TD></TR></TABLE> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left"><B>Re:</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Tenable Holdings, Inc. </B></TD></TR></TABLE>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left"><B>&nbsp;</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Draft Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1</FONT> </B></TD></TR></TABLE>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left"><B>&nbsp;</B></TD>
<TD ALIGN="left" VALIGN="top"><B>Submitted April&nbsp;27, 2018 </B></TD></TR></TABLE>
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<TD WIDTH="5%" VALIGN="top" ALIGN="left"><B>&nbsp;</B></TD>
<TD ALIGN="left" VALIGN="top"><B>CIK No.&nbsp;0001660280 </B></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Ladies and Gentlemen: </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">On behalf of Tenable Holdings, Inc. (the &#147;<B><I>Company</I></B>&#148;), we are providing this letter in response to the comments of the staff of the U.S.
Securities and Exchange Commission&#146;s Division of Corporation Finance (the &#147;<B><I>Staff</I></B>&#148;) contained in its letter, dated May&nbsp;24, 2018 (the &#147;<B><I>Comment Letter</I></B>&#148;), relating to the Company&#146;s Draft
Registration Statement on Form <FONT STYLE="white-space:nowrap">S-1,</FONT> confidentially submitted on April&nbsp;27, 2018 (the &#147;<B><I>Draft Registration Statement</I></B>&#148;). </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company is concurrently confidentially submitting a revised draft registration statement (the &#147;<B><I>Amended DRS</I></B>&#148;), which reflects
changes made in response to certain of the comments contained in the Comment Letter. We are also sending the Staff a copy of this letter, along with four copies of the Amended DRS marked to show all changes from the Draft Registration Statement.
</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The numbering of the paragraphs below corresponds to the numbering of the comments contained in the Comment Letter, which for your convenience we have
incorporated into this response letter in italics. Page references in the text of this response letter correspond to the page numbers of the Amended DRS. Capitalized terms used in this letter but not otherwise defined in this letter shall have the
meanings set forth in the Amended DRS. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto,
CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650) <FONT STYLE="white-space:nowrap">843-5000&nbsp;&nbsp;f:</FONT> (650) <FONT
STYLE="white-space:nowrap">849-7400&nbsp;&nbsp;cooley.com</FONT> </P>

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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Two </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Prospectus Summary </U></P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Overview, page 1 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>1.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>When discussing your results of operations on page 2 you disclose free cash flow but do not disclose the corresponding GAAP measure. We note similar concerns with your discussion on page 77. Please revise to disclose
the most directly comparable GAAP measure with greater prominence. Refer to Item 10(e)(1)(i)(A) of Regulation <FONT STYLE="white-space:nowrap">S-K</FONT> and Question 102.10 of the <FONT STYLE="white-space:nowrap">Non-GAAP</FONT> Compliance and
Disclosure Interpretations. </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on pages 2 and 83 of the
Amended DRS accordingly. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>2.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>You disclose that in both 2016 and 2017 your recurring revenue represented 86% of total revenues. Please disclose how you define recurring revenues. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on pages 2 and 83 of the Amended DRS accordingly. </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>3.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please clarify the number of Fortune 500 and Global 2000 organizations with enterprise subscriptions for the period ended December&nbsp;31, 2017 and disclose how you define an enterprise customer. In addition,
disclose the average annual contract value for your Fortune 500 and Global 2000 customers for the period ended December&nbsp;31, 2017. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on pages 2 and 83 of the Amended DRS to clarify how the Company defines an
enterprise customer and on pages 2, 83 and 94 to disclose the number of Fortune 500 and Global 2000 organizations that were enterprise platform customers for the period ended December&nbsp;31, 2017. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">With respect to the average annual contract value for the Company&#146;s Fortune 500 and Global 2000 customers, the Company respectfully acknowledges the
Staff&#146;s comment and is supplementally providing to the Staff under separate cover a response to this inquiry, pursuant to Rule 418 under the Securities Act of 1933, as amended. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Selected Risks Affecting Our Business, page 5 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>4.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>To provide context as to the concentration of ownership in Tenable, please disclose the percentage of your common stock held by your existing officers, directors and principal stockholders. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page 6 of the Amended DRS accordingly. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Three </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Risk Factors </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Risks Related to Our Business and Industry </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Organizations may be reluctant&#133;, page 20 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>5.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please provide examples of the types of organizations that are reluctant to use cloud solutions for cyber security. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page 20 of the Amended DRS accordingly. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>We rely on our third-party channel partner&#133;, page 20 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>6.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Here or in the Business section, please disclose the material terms of your agreement with Ingram Micro, Inc. including the term and any material termination provisions. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page 21 of the Amended DRS accordingly. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Dilution, page 48 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>7.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>We note that you include $50.2&nbsp;million of deferred commissions in your total tangible assets. Please tell us how you determined that deferred commissions are tangible assets for purposes of your dilution
calculation. </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page 48 of the Amended DRS to remove
deferred commissions from its total tangible assets for purposes of its dilution calculation, consistent with Section&nbsp;8320 of the Staff&#146;s Financial Reporting Manual related to the exclusion of deferred costs from tangible assets. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Selected Consolidated Financial Data </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U><FONT
STYLE="white-space:nowrap">Non-GAAP</FONT> Financial Measures </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Calculated Billings, page 53 </U></P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>8.</I></TD>
<TD ALIGN="left" VALIGN="top"> <P ALIGN="left" STYLE=" margin-top:0pt ; margin-bottom:0pt; font-family:Times New Roman; font-size:10pt"><I>You disclose on page 18 that many of your customers have the right to terminate their agreements. Please
revise to disclose the extent to which your subscription and maintenance contracts are cancellable. Also, tell us the amount or percentage of arrangements entered into in 2016 and 2017 that are multi-year contracts and whether you typically invoice
these customers for the full </I></P></TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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contractual amount in advance. To the extent that the multi-year arrangements have a significant impact on the comparability of your billings in a given period please revise to explain the
impact. </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company supplementally advises the Staff that, although selected customers and partners could take the position that
provisions within their customer agreements give them the right to terminate their agreement with the Company or allege a material breach of their agreement due to or in connection with the sale of the Company&#146;s common stock, customers are
typically invoiced in advance, inclusive of multi-year contracts, and the Company&#146;s contracts generally do not provide for refunds. The Company has revised its disclosure on page 18 of the Amended DRS accordingly. As disclosed on page 57 of the
Amended DRS, one year arrangements are the primary subscription arrangement. The Company additionally advises the Staff that it has revised its disclosure on page 53 of the Amended DRS to disclose the <FONT STYLE="white-space:nowrap">non-GAAP</FONT>
metric of calculated current billings, rather than calculated billings. The Company believes that multi-year arrangements may create some variability in the comparability of billings in a given period and that the calculated current billings metric
improves comparability by removing the impact of multi-year contracts. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Management&#146;s Discussion and Analysis of Financial Condition and Results of
Operations</U> </P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Overview, page 55 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>9.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please explain to us how presenting the cumulative free Nessus users provides meaningful information. For each period presented disclose the number of free Nessus users and the number of Nessus Professional users
that are active. Tell us how you determine a user is active and tell us whether any metrics are used to monitor the extent to which free Nessus users convert to Nessus Professional or other enterprise platform offerings. If so, revise to include
quantified disclosure of such metrics. Refer to Item 303(a)(3) of Regulation <FONT STYLE="white-space:nowrap">S-K</FONT> and Section III.B.1 of SEC Release <FONT STYLE="white-space:nowrap">No.&nbsp;33-8350.</FONT> </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that, as disclosed in the Draft Registration Statement, the Company believes that its community of Nessus users,
cultivated over the past 20 years, represents an important data asset that, along with the Company&#146;s internal researchers, provides real-time feedback on vulnerability data, insight and learnings that the Company uses to expand its assessment
capabilities and coverage and improve its current products and products in development. The Company also considers the number of Nessus users, including the cumulative numbers of free Nessus users, to be representative of the Company&#146;s brand
recognition among cybersecurity professionals and that continued growth in this number suggests broader awareness among customers. The Company believes that it has not yet fully penetrated its potential market opportunity to sell its products to
customers who </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Five </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
are currently only users of Nessus Home and that expansion of its relationships with these users represents an important growth strategy. However, as described on page 57 of the Amended DRS, the
Company expects many of its Nessus Home users to continue to use that product and not upgrade to Nessus Professional or the Company&#146;s enterprise platform offerings. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company further advises the Staff that it only monitors downloads of its Nessus Home product by unique email addresses but does not monitor whether a
Nessus Home user is actively using the product, nor does the Company have the ability to systematically track whether or the rate at which Nessus Home users upgrade to Nessus Professional or the Company&#146;s enterprise platform offerings. The
Company also advises the Staff that it does not consider the cumulative number of free Nessus users to be a key operating or financial metric and does not intend to regularly report this number for each financial period in the future. As described
in the preceding paragraph, the Company has included the cumulative user number as of December&nbsp;31, 2017 in the Draft Registration Statement primarily to give an indication to investors of the growth and scale of its thought leadership and brand
awareness. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Factors Affecting Our Performance </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>New
Enterprise Platform Customer Acquisition, page 57 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>10.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>You disclose that you had over 24,000 total customers as of December&nbsp;31, 2017. Please revise to disclose the total customer count for each period presented. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that it does not view its total number of customers as a key operating metric and does not intend to report this
number regularly for each quarterly period in the future. Rather, the Company has included this information throughout the Draft Registration Statement to give an indication to investors of the breadth of its current customer base and the potential
of the Company&#146;s business model to generate additional revenue opportunities by retaining and expanding revenue from these existing customers. The Company expects to report the total number of customers on an annual basis. Accordingly, the
Company has revised its disclosure on page 59 of the Amended DRS to remove the number of total customers from this section. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">For the reasons described in
the Draft Registration Statement, the Company views the number of enterprise platform customers and the number of customers with $100,000 and greater in annual contract value as meaningful operating metrics, as the Company believes that these
customers represent the most material revenue growth opportunities. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Six </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Retaining and Expanding Revenue from Existing Customers, page 58 </U></P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>11.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>You disclose that your dollar-based net expansion rate exceeded 120% at December&nbsp;31, 2016 and 2017. Please revise to disclose the actual percentage for each period presented. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page 61 of the Amended DRS accordingly. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Critical Accounting Policies and Estimates </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Stock-Based Compensation, page 71 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>12.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Regarding the summary of stock-based awards provided on page 73, please describe for us the factors that contributed to significant fluctuations in the fair values from <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap">period-to-</FONT></FONT> period, including any intervening events within the company or changes in your valuation assumptions or methodology. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that the fair value of the Company&#146;s common stock has been determined by the Company&#146;s board of directors
as of the date of each equity award-based grant. As disclosed in the Draft Registration Statement, the Company&#146;s estimated fair value of each option award on the grant date is based upon the Black-Scholes option pricing model. The Company
advises the Staff that its methodology to calculate the fair value of each option award has been consistent from period to period.</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">In valuing the
Company&#146;s common stock, the fair value of the business, or enterprise value, was first determined using the income and market approaches described in the AICPA&#146;s practice aid referenced in the Draft Registration Statement. Once an
enterprise value is determined, the Company utilizes a hybrid of the option pricing method (&#147;<B><I>OPM</I></B>&#148;) and the probability-weighted expected return method (&#147;<B><I>PWERM</I></B>&#148;) to allocate this value to the various
classes and series of its capital stock. The PWERM approach employs various market approach calculations depending upon the likelihood of various discrete future liquidity scenarios, including initial public offering (&#147;<B><I>IPO</I></B>&#148;)
scenarios and <FONT STYLE="white-space:nowrap">non-IPO</FONT> scenarios. The probability and timing of each scenario are based upon discussions between the Company&#146;s board of directors and management team. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">In its application of the hybrid method, the Company relies on the PWERM to allocate the value of equity under a near-term liquidity scenario and the OPM to
allocate the value of equity under a long-term liquidity scenario. The projected equity values relied upon in the PWERM scenario are based on (1)&nbsp;guideline IPO transactions involving companies that are considered broadly comparable to the
Company and (2)&nbsp;the </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Seven </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
Company&#146;s expectation of the <FONT STYLE="white-space:nowrap">pre-money</FONT> valuation needed to achieve to consider an IPO as a viable exit strategy. The projected equity values relied
upon in the OPM are based on a weighted average indication of the value using the discounted cash flow method, which is an income approach, and the guideline public company method, which is a market approach. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Significant factors considered by the Company&#146;s board of directors in determining the fair value of the Company&#146;s common stock for equity grant
dates from January&nbsp;1, 2017 to the date of the Amended DRS include: </P> <P STYLE="font-size:12pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
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<TR>
<TD WIDTH="9%"></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD></TD>
<TD VALIGN="bottom" WIDTH="3%"></TD>
<TD WIDTH="68%"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:8pt">
<TD VALIGN="bottom" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman"><B>Valuation</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:33.75pt; display:inline; font-size:8pt; font-family:Times New Roman; "><B>Date</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Fair<BR>Value<BR>per<BR>Ordinary<BR>Share</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Estimated<BR>Probability<BR>of&nbsp;Liquidity<BR>Event<BR>Included in<BR>PWERM</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Significant Events During Quarter Prior to
Valuation</B></P></TD></TR>


<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">December&nbsp;1, 2016</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$4.25</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">30%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Company in final stages of search for new Chief Executive Officer</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Acquisition of container
security software company and rights to web application scanning software</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Continued development of Tenable.io</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">April&nbsp;1,&nbsp;2017</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$5.96</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">35%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Revenue for the first quarter of 2017 increased 58% over first quarter of
2016</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Company hired new
Chief Executive Officer, Amit Yoran, Chief Revenue Officer, John Negron, and Chief Marketing Officer, Jennifer Johnson</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Launch of Tenable.io</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;International headquarters opened in Dublin, Ireland</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">July&nbsp;1, 2017</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$7.75</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">35%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Revenue for the second quarter of 2017 increased 53% over second quarter of
2016</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Launch of new cyber
exposure marketing strategy, expanding on the Company&#146;s prior vulnerability management marketing strategy</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Initial sales of Tenable.io to enterprise customers, including a sale to a Fortune 50 enterprise
customer</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Asia-Pacific
(APAC) sales headquarters opened in Australia</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Comparable public company share prices continued to
increase</P></TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650) 843-5000&nbsp;&nbsp;f: (650)
849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Eight </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TD VALIGN="bottom" NOWRAP> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:8pt; font-family:Times New Roman"><B>Valuation</B></P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; border-bottom:1.00pt solid #000000; width:33.75pt; display:inline; font-size:8pt; font-family:Times New Roman; "><B>Date</B></P></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Fair<BR>Value<BR>per<BR>Ordinary<BR>Share</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"><B>Estimated<BR>Probability<BR>of&nbsp;Liquidity<BR>Event<BR>Included in<BR>PWERM</B></TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="bottom" ALIGN="center" STYLE="border-bottom:1.00pt solid #000000"> <P STYLE="margin-top:0pt; margin-bottom:1pt; font-size:8pt; font-family:Times New Roman" ALIGN="center"><B>Significant Events During Quarter Prior to
Valuation</B></P></TD></TR>


<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">October&nbsp;1, 2017</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$9.66</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">40%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Revenue for the third quarter of 2017 increased 45% over third quarter of
2016</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Introduction of
container security and web application scanning modules for Tenable.io</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Comparable public company share prices continued to increase</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">January&nbsp;1, 2018</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$10.97</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">50%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Revenue for the fourth quarter of 2017 increased 50% over fourth quarter of
2016</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Company reached
nearly 1,000 employees</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Board appointed its first independent director, A. Brooke Seawell</P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Announcement of Industrial
Security partnership with Siemens</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Tax Cuts and Jobs Act passed, which the Company believes may reduce tax expense in long-term
forecasts</P></TD></TR>
<TR STYLE="font-size:1pt">
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR BGCOLOR="#cceeff" STYLE="page-break-inside:avoid ; font-family:Times New Roman; font-size:10pt">
<TD VALIGN="top">April&nbsp;1,&nbsp;2018</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">$14.06</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top">60%</TD>
<TD VALIGN="bottom">&nbsp;&nbsp;</TD>
<TD VALIGN="top"> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Revenue for the first quarter of 2018 increased 46% over first quarter of
2017</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Board appointed its
second independent director, Arthur W. Coviello, Jr.</P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="margin-top:0pt; margin-bottom:1pt; margin-left:4.00em; text-indent:-1.50em; font-size:10pt; font-family:Times New Roman">&#149;&#8195;&#8202;Company initiated discussions with underwriters and counsel for a potential IPO</P></TD></TR>
</TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Business </U></P> <P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Customers,
page 88 </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>13.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please disclose the objective criteria you have used in selecting the representative customers you identified by name, which will assist investors in understanding their significance to you. </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that the representative customers identified by name on page 94 of the Amended DRS have annual bookings of more
than $30,000. The Company has revised the disclosure accordingly. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Certain Relationships and Related Party Transactions </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Investors&#146; Rights, Management Rights, Voting and <FONT STYLE="white-space:nowrap">Co-Sale</FONT> Agreements, page 117</U> </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Nine </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>14.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please disclose the names of the related parties to the investors&#146; rights agreement and the basis on which they are related parties. Refer to Item 404(a)(1) of Regulation
<FONT STYLE="white-space:nowrap">S-K.</FONT> </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page
126 of the Amended DRS accordingly. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Consolidated Financial Statements </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Note 2. Summary of Significant Accounting Policies </U></P>
<P STYLE="margin-top:6pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Revenue Recognition, page <FONT STYLE="white-space:nowrap">F-8</FONT> </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>15.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>You disclose on page 56 that you sell your enterprise platform offerings to distributors, which in turn sell to resellers, which then sell to end users, which you call customers. Please clarify your disclosures to
state the timing at which you begin recognizing revenues and tell us how you determine that control has transferred. Refer to ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-25</FONT></FONT></FONT> and ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-50-17.</FONT></FONT></FONT> </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and respectfully advises the Staff that for purposes of Management&#146;s Discussion and Analysis of
Financial Condition and Results of Operations, the Company has defined <FONT STYLE="white-space:nowrap">end-users</FONT> as &#147;customers.&#148; For accounting purposes, when selling through its <FONT STYLE="white-space:nowrap">two-tier</FONT>
distribution system, the Company has identified the distributor as its direct customer and the <FONT STYLE="white-space:nowrap">end-user</FONT> as its indirect customer. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company&#146;s software licenses and access to cloud-based solutions are delivered via electronic keys. The Company considered the guidance under ASC <FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-25</FONT></FONT></FONT> and determined that control is transferred to the distributor and through to the
<FONT STYLE="white-space:nowrap">end-user</FONT> at the time that the electronic keys are delivered to the <FONT STYLE="white-space:nowrap">end-user.</FONT> The Company begins to recognize revenue when the electronic keys are delivered as that is
when the distributor has the ability to direct the use of and obtain substantially all of the benefits from the cybersecurity vulnerability detection service provided through the Company&#146;s software and cloud-based solutions. The Company has
revised its disclosure on pages 62, 77 and <FONT STYLE="white-space:nowrap">F-9</FONT> of the Amended DRS accordingly. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>16.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please provide us the following information regarding your perpetual license arrangements and revise your disclosures as appropriate: </I></TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>Tell us if you have identified the material right as a separate performance obligation. If you have combined the material right with the perpetual license and maintenance, please tell us why you believe this is
appropriate. Refer to ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-42.</FONT></FONT></FONT></I> </TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Ten </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>

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<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>Tell us the period of time over which you are recognizing revenue for your combined performance obligation of the perpetual license and initial maintenance. If this period is longer than your initial maintenance
period, please tell us why you believe this is appropriate.</I> </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>Tell us the period of time over which you are recognizing revenue for your material right. If this period begins prior to the time the additional maintenance is transferred or when the material right expires, tell us
why you believe this is appropriate. Refer to ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-42.</FONT></FONT></FONT></I> </TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that its perpetual licenses are generally sold with one or more years of maintenance, which includes ongoing
software updates and the ongoing ability to identify the latest cybersecurity vulnerabilities. The vulnerability updates occur frequently, at times with multiple updates occurring daily. The Company considered the guidance under ASC <FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-19.b</FONT></FONT></FONT> and <FONT STYLE="white-space:nowrap">25-21</FONT> as well as ASC <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-140D</FONT></FONT></FONT> through F (Example 10 Case C, combined anti-virus software with unspecified software updates). The Company determined that the promise to transfer the
software license and the ongoing maintenance are not separately identifiable under ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-21,</FONT></FONT></FONT> because: </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">The software license and the ongoing software and vulnerability updates are significantly integrated in order to provide the ability to detect cybersecurity vulnerabilities. </TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">The ongoing vulnerability updates significantly modify the licensed software as they allow for the identification of newly discovered cybersecurity vulnerabilities that the software was previously unable to detect.
</TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">The licensed software is highly dependent on the vulnerability updates in order to provide the ability to detect cybersecurity vulnerabilities and without such upgrades, the value of the licensed software would
deteriorate rapidly. As such, the Company cannot satisfy its obligations to transfer the license and maintenance independent of one another. </TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Since the perpetual license and maintenance are effectively inputs to a combined item, the Company concluded that they should be considered one combined
performance obligation to provide the ability to detect cybersecurity vulnerabilities. The Company&#146;s perpetual license arrangements generally provide for maintenance renewal options that result in a material right related to the perpetual
license as the customer can renew maintenance for an amount less than the fee in the initial contract (as it does not have to pay consideration for the license in the maintenance renewals). The Company concluded that the material right is a separate
performance obligation in the Company&#146;s contracts with its customers. Under ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-45</FONT></FONT></FONT> and the Basis for Conclusions
paragraphs BC392 through BC395 of ASU <FONT STYLE="white-space:nowrap">2014-09,</FONT> the Company applies the practical alternative to allocate consideration to the renewal option. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Eleven </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company considered the factors provided in paragraph <FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-45</FONT></FONT></FONT> to apply the practical alternative including: </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">The additional goods and services in the renewal options are similar to those provided in the initial contract </TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="5%">&nbsp;</TD>
<TD WIDTH="2%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">The renewal options&#146; terms and conditions related to goods and services are the same as the original contract </TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company concluded its maintenance renewal options met these criteria because services provided related to the maintenance (detection of cybersecurity
vulnerabilities) are the same, with the same terms and conditions as the initial maintenance sold with the software license. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Under the practical
alternative, the Company estimates a hypothetical transaction price based on its best estimate of the number of years that a customer will renew. In accordance with ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap">606-10-55-45,</FONT></FONT></FONT> and as illustrated in paragraphs ASC <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-343</FONT></FONT></FONT> through <FONT
STYLE="white-space:nowrap">55-352</FONT> (Example 51), the hypothetical transaction price is then allocated to the goods and services expected to be provided, including any optional goods or services resulting from contract renewals. As the Company
has concluded that the goods and services provided under its perpetual license and maintenance arrangements is a combined performance obligation to detect cybersecurity vulnerabilities over a period of time, and the criteria in ASC <FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-45</FONT></FONT></FONT> are met, the Company allocates the transaction price between the cybersecurity license provided in the initial contract
and the material right related to expected contract renewals based on the consideration the Company expects to receive for all services it expects to provide to the customer under the initial contract and expected renewal contracts at a discount.
</P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company believes that it has appropriately considered the guidance in <FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT
STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">ASC-606-10-55-42,</FONT></FONT></FONT></FONT> as well as the guidance in ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-19,</FONT></FONT></FONT> ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-25-21,</FONT></FONT></FONT> ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-140D</FONT></FONT></FONT> through F and ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">606-10-55-45,</FONT></FONT></FONT> in determining how it identifies performance obligations and recognizes revenue related to perpetual licenses,
perpetual license maintenance and the related material right. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company has revised its disclosure on pages 62, 77 and
<FONT STYLE="white-space:nowrap">F-9</FONT> of the Amended DRS to describe the application of the practical alternative, estimation of a hypothetical transaction price, the allocation of the transaction price and the recognition of the transaction
price over the estimated economic life of the contract. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Note 7. Redeemable Convertible Preferred Stock and Common Stock, page <FONT
STYLE="white-space:nowrap">F-16</FONT></U> </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>17.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>You disclose that all preferred stock will automatically convert upon a qualifying initial public offering. Please disclose how a qualifying initial public offering is defined and any conditional provisions if this
offering does not constitute a qualified initial public offering. </I></TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650) 843-5000&nbsp;&nbsp;f: (650)
849-7400&nbsp;&nbsp;cooley.com </P>


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 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Twelve </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and has revised its disclosure on page <FONT
STYLE="white-space:nowrap">F-18</FONT> of the Amended DRS accordingly. The Company supplementally advises the Staff that it expects its preferred stock to automatically convert to common stock in connection with the proposed offering in accordance
with the terms of its existing certificate of incorporation, and it does not expect an outcome that would result in the offering being completed without such conversion. </P>
<P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>Note 10. Income Taxes, page <FONT STYLE="white-space:nowrap">F-20</FONT> </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>18.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please tell us how where the impact of the remeasurement of deferred tax assets and liabilities resulting from the 2017 Tax Cuts and Jobs Act and the impact from the adoption of ASC 606 are included in your rate
reconciliation. Refer to Rule <FONT STYLE="white-space:nowrap">4-08(h)(2)</FONT> of Regulation <FONT STYLE="white-space:nowrap">S-X</FONT> and ASC
<FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap"><FONT STYLE="white-space:nowrap">740-10-50-12.</FONT></FONT></FONT> </I></TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully advises the Staff that the remeasurement of the Company&#146;s deferred tax assets and liabilities resulted in the Company reducing
its overall deferred tax asset by $14.1&nbsp;million, with a corresponding reduction to the Company&#146;s valuation allowance. These offsetting entries resulted in no impact on the Company&#146;s income tax provision and net loss for the year ended
December&nbsp;31, 2017. The Company has disclosed the impact of the remeasurement of its deferred tax assets and liabilities in its rate reconciliation table on page <FONT STYLE="white-space:nowrap">F-23</FONT> of the Amended DRS under the
&#147;Revaluation of U.S. Deferred Income Taxes&#148; caption. The impact of the remeasurement on the rate reconciliation was 34.5%. The impact of the reduction to the Company&#146;s valuation allowance is reflected in the rate reconciliation table
under the &#147;Valuation allowance&#148; caption. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company further advises the Staff that adoption of ASC 606 did not have any impact on the
Company&#146;s tax rate reconciliation, as the Company recorded an increase in the balance of its deferred tax assets related to deferred revenue on January&nbsp;1, 2017 by $14.7&nbsp;million, with a corresponding increase in its valuation
allowance. </P> <P STYLE="margin-top:18pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman"><U>General </U></P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>19.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please supplementally provide us with copies of all written communications, as defined in Rule 405 under the Securities Act, that you, or anyone authorized to do so on your behalf, present to potential investors in
reliance on Section&nbsp;5(d) of the Securities Act, whether or not they retain copies of the communications. </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">In response to the
Staff&#146;s comment, the Company advises the Staff that it has commenced &#147;testing the waters&#148; meetings with potential investors. Accordingly, the Company is supplementally providing to the Staff a copy of the presentation that the Company
has used in these meetings with qualified institutional buyers or institutional </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


<p Style='page-break-before:always'>
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<IMG SRC="g548092g0606130054321.jpg" ALT="LOGO">
 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Thirteen </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">
accredited investors. The Company further advises the Staff that it will supplementally provide the Staff with copies of any additional written communications of the type referenced in the
Staff&#146;s comment. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>20.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please supplementally provide us with copies of any graphical materials or artwork you intend to use in your prospectus. Upon review of such materials, we may have further comments. For guidance, refer to Question
101.02 of our Securities Act Forms Compliance and Disclosure Interpretations. </I></TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company acknowledges the Staff&#146;s comment and
confirms that, once available and prior to printing and distributing its preliminary prospectus to investors, it will supplementally provide the Staff with any <FONT STYLE="white-space:nowrap">mock-ups</FONT> of any pages that include any graphics,
photographs, and the related captions or other artwork including logos. </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%">&nbsp;</TD>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><I>21.</I></TD>
<TD ALIGN="left" VALIGN="top"><I>Please disclose the source of the following assertions in your prospectus: </I></TD></TR></TABLE> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>You are the first and only provider of solutions for a new category of cybersecurity called Cyber Exposure (pages 1, 55, 76 and 83);</I> </TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>You are the first and only Cyber Exposure platform designed to provide broad visibility and deep insights into cyber exposure across the entire modern attack surface (pages 4, 57, 80); and</I> </TD></TR></TABLE>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>You have market leadership in Cyber Exposure (pages 5, 60 and 82). </I> </TD></TR></TABLE> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">As described in the Draft
Registration Statement, the Company believes it has defined a new market category, which the Company calls Cyber Exposure, that goes beyond the vulnerability management market in which the Company and its competitors have traditionally competed. As
described in the Draft Registration Statement, the Company believes that the new category of Cyber Exposure more accurately captures the need for organizations to manage and measure their cybersecurity risk in the digital era. The digital era, as
described in the Draft Registration Statement, requires monitoring of both traditional assets, such as laptops and servers, and modern assets, such as cloud workloads and containers, as well as an understanding of how to prioritize and address
cybersecurity risk. The Company believes that it has created the Cyber Exposure market by expanding the traditional vulnerability management market and building on its vulnerability management expertise, including its significant data asset provided
by its Nessus community cultivated over 20 years and the Tenable Research team, to develop new solutions that identify cybersecurity risk across both traditional and modern IT assets and provide analytics that translate vulnerability data into
business insight. </P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


 <P STYLE="margin-top:0pt;margin-bottom:0pt">


<IMG SRC="g548092g0606130054321.jpg" ALT="LOGO">
 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Fourteen </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">As discussed in the Draft Registration Statement, as the Company&#146;s customers have embraced digital
transformation by modernizing their IT infrastructure and adopting cloud or hybrid cloud architectures, the Company&#146;s offerings have similarly evolved to address the increased IT complexity and cybersecurity risk associated with these modern IT
assets. As disclosed on page 98 of the Amended DRS, while the Company is aware of different vulnerability management tools that address different parts of security, the Company is not aware of any other provider of vulnerability management solutions
that combines visibility across both traditional and modern IT assets with analytics to prioritize and measure cybersecurity risk. Furthermore, in April 2017, Forrester Research Inc. recognized the Company as having the only platform included in
their report on vulnerability management tools that delivered all seven identified essential features.<SUP STYLE="font-size:85%; vertical-align:top">1</SUP> </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="9%">&nbsp;</TD>
<TD WIDTH="3%" VALIGN="top" ALIGN="left">&#149;</TD>
<TD WIDTH="1%" VALIGN="top">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top"><I>You have been an integral part of the cybersecurity market for nearly two decades (pages 2 and 76).</I> </TD></TR></TABLE>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">The Company respectfully submits that one of the Company&#146;s <FONT STYLE="white-space:nowrap">co-founders</FONT> created Nessus, a vulnerability assessment
solution, in 1998. As disclosed in the Draft Registration Statement, Nessus has had approximately two million cumulative free users, defined as a unique email address used to download Nessus, from 2004 to 2017. Since Nessus was created, the Company
has received a number of industry awards and recognitions. In 2002, the SANS Institute, an information security and cybersecurity training company, published reports recommending Nessus as a vulnerability management tool. PC Magazine named Nessus as
the best open-source security tool in 2003 and included it on its list of the most important open-source apps of all time. In 2004, Network Computing Magazine named the Company&#146;s predecessor entity a &#147;company to watch.&#148; Further, the
Company&#146;s solutions were finalists for the SC Magazine Awards, presented by a leading cybersecurity magazine, from 2007 to 2015 and won awards in 2013, 2014, 2015 and 2016. </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">* * * * </P> <P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<P STYLE="line-height:8.0pt;margin-top:0pt;margin-bottom:2pt;border-bottom:1px solid #000000;width:10%">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="2%" VALIGN="top" ALIGN="left"><SUP STYLE="font-size:85%; vertical-align:top">1</SUP>&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Forrester Research Inc., Vendor Landscape for Vulnerability Management, dated April&nbsp;27, 2017. </TD></TR></TABLE>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>


<p Style='page-break-before:always'>
<HR  SIZE="3" style="COLOR:#999999" WIDTH="100%" ALIGN="CENTER">


 <P STYLE="margin-top:0pt;margin-bottom:0pt">


<IMG SRC="g548092g0606130054321.jpg" ALT="LOGO">
 </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Page Fifteen </P> <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P>
 <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Please contact me at (650) <FONT STYLE="white-space:nowrap">843-5049</FONT> with any questions or further
comments regarding our responses to the Staff&#146;s comments. </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Sincerely, </P>
<P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">/s/ Eric C. Jensen </P> <P STYLE="margin-top:12pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman">Eric C. Jensen </P>
<P STYLE="font-size:6pt;margin-top:0pt;margin-bottom:0pt">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">cc:</TD>
<TD ALIGN="left" VALIGN="top">Amit Y. Yoran, Tenable Holdings, Inc. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Stephen A. Riddick, Tenable Holdings, Inc. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Brian F. Leaf, Cooley LLP </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Madison A. Jones, Cooley LLP </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Michael C. Labriola, Wilson Sonsini Goodrich&nbsp;&amp; Rosati, P.C. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Mark R. Fitzgerald, Wilson Sonsini Goodrich&nbsp;&amp; Rosati, P.C. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Megan J. Baier, Wilson Sonsini Goodrich&nbsp;&amp; Rosati, P.C. </TD></TR></TABLE>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE; font-family:Times New Roman; font-size:10pt" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR style = "page-break-inside:avoid">
<TD WIDTH="4%" VALIGN="top" ALIGN="left">&nbsp;</TD>
<TD ALIGN="left" VALIGN="top">Mark G.C. Bass, Wilson Sonsini Goodrich&nbsp;&amp; Rosati, P.C.<B> </B> </TD></TR></TABLE> <P STYLE="font-size:12pt; margin-top:0pt; margin-bottom:0pt">&nbsp;</P>
 <p STYLE="margin-top:0pt;margin-bottom:0pt ; font-size:8pt">&nbsp;</P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">Cooley
LLP&nbsp;&nbsp;&nbsp;&nbsp;3175 Hanover Street&nbsp;&nbsp;&nbsp;&nbsp;Palo Alto, CA&nbsp;&nbsp;&nbsp;&nbsp;94304-1130 </P> <P STYLE="margin-top:0pt; margin-bottom:0pt; font-size:10pt; font-family:Times New Roman" ALIGN="center">t: (650)
843-5000&nbsp;&nbsp;f: (650) 849-7400&nbsp;&nbsp;cooley.com </P>

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end
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
