Google, Yahoo, IAC, AOL, and Lycos -- the major Internet search companies other than Microsoft -- on Wednesday filed a motion to compel the Software Rights Archive (SRA) to reveal who is behind its 2-year-old patent lawsuit against them.

In November 2007, SRA, a patent holding company, sued the search companies for patent infringement in the Eastern District of Texas, a venue long popular with patent litigants. SRA claims that the search engines are violating its patent titled "Method and Apparatus for Indexing, Search, and Displaying Data," among others.

Last July, Google, Yahoo, IAC, AOL, and Lycos filed a countersuit in California seeking a declaratory judgment, alleging that the patents claimed by are invalid. SRA is contesting that claim.

Google on Friday declined to comment about the case.

With the Texas and California lawsuits in play, Google and its fellow defendants this week took the offensive. The search companies are seeking documents about the ownership structure of SRA to determine who is bankrolling the patent litigation and to uncover information that might aid in their defense.

"... Software Rights Archive disclosed that there is a 'stakeholder' behind it, but refused to disclose the identity of this controlling 'stakeholder,'" the complaint states. "Software Rights Archive appears to share the same address as Altitude Capital, however."

Altitude Capital Partners identifies itself as "a leading private investment firm focused on investing $250 million of capital in businesses which own compelling intellectual property assets."

According to the search companies, it specializes in "venture-funded litigation."

In 2007, on the Techdirt blog, Mike Mashnik described Altitude Capital Partners as "another example of a company that failed in the marketplace wanting to take money away from those who actually did deliver what customers wanted."

The search engines accuse SRA and Altitude Capital of stonewalling their document requests. A recent subpoena filed by the search engines was answered by Altitude Capital with 227 pages, "almost entirely comprised of public documents." Missing was information about SRA's relationship to Altitude Capital and its efforts to monetize patents related to SRA's lawsuit against the search engines.

Coincidentally, a January article in The New York Law Journal finds that despite the economic downturn, business for some lawyers is booming.

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