Mail Stop 4561

October 20, 2005


Stephen Green
Senior Vice President and General Counsel
IHS, Inc.
15 Inverness Way East
Englewood, CO  80112

Re:  	IHS, Inc.
	Amendment No. 6 to Form S-1
		Filed October 6, 2005
	File No. 333-122565

Dear Mr. Green:

      We have reviewed your responses and, as indicated in our
October 18, 2005 letter, we have the following comments.

General
1. We have reviewed your response to prior comment 2 in our letter
dated September 15, 2005. In particular, we note that the Amended
and
Restated Stock Purchase Agreement contemplates an unregistered
sale
of securities from the selling stockholders to General Atlantic
upon
closing of the initial public offering.  We do not agree that
Section
4(2) is available to the unregistered transaction since this
exemption is available only to the issuer (i.e., IHS).  With
respect
to your argument that Section 4(1) is available, please provide us
with a more comprehensive analysis as to why Section 4(1) is
available in these circumstances.

Exhibit Index
2. We note that you have not filed the November 2004 agreement
between Holland America Investment Corporation wherein HAIC
contributed substantially all of its assets to you in exchange for
your common stock, which was then distributed to the selling
shareholders.  As this agreement was entered into within the last
two
years, it should be filed as a material agreement under Item
601(b)(10) of Regulation S-K.

    As appropriate, please amend your registration statement in
response to these comments. You may wish to provide us with marked
copies of the amendment to expedite our review.  Please furnish a
cover letter with your amendment that keys your responses to our
comments and provides any requested supplemental information.
Detailed cover letters greatly facilitate our review.  We may have
additional comments based on reviewing your amendment and
responses
to our comments.

    You may contact Lisa Mitrovich, Assistant Chief Accountant, at
202-551-3453, if you have questions regarding comments on the
financial statements and related matters.  Please address all
other
comments to Maryse Mills-Apenteng at 202-551-3457.  If you require
further assistance you may contact the undersigned at 202-551-
3730.

								Sincerely,



								Barbara C. Jacobs
								Assistant Director

cc:	Via facsimile:  212-450-3662
      Richard J. Sandler, Esq.
      Mark Schwartz, Esq.
      Davis Polk & Wardwell



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Stephen Green
IHS, Inc.
October 20, 2005
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