What do Linux vendors want with those former Microsoft graphics patents?

The Wall Street Journal is reporting that a group of open-source backers is poised to purchase 22 graphics patents formerly the property of Microsoft.

The patents in question seem to include some or all of the 3D-graphics-related ones that Microsoft purchased from SGI in 2002. Microsoft sold these patents earlier this year to a third-party patent broker, Allied Security Trust (AST). The Journal reported on September 8 that AST is selling the patents to the Open Invention Network (OIN), a group of companies including IBM, Novell, Red Hat and Sony. The gist of the Journal's story is OIN members want to buy the graphics patents to head off potential patent trolls who might be interested in acquiring them to use against open-source vendors.

I've asked OIN, AST and Microsoft for more information and have yet to hear back from any of them.

Update: Microsoft responded Tuesday afternoon. Spokesperson Michael Marinello sent the following statement:

"We sold 22 patents to AST in July 2009. The terms were confidential. We acquired these patents several years ago as part of a larger business agreement with SGI.

"We are constantly evaluating our patent portfolio – which recently received top ranking in the software industry -- to ensure its makeup fits into the business goals of the organization. These patents were deemed to be non-core to our business and non-essential for our IP portfolio.  When an interested buyer for this technology was identified, after discussing it both internally and with the potential buyer, we felt this was the right direction to go in relating to these specific patents."

Marinello advised me to get in touch with AST, as they own the patents now. I still have not heard back from AST or OIN. But OIN issued a press release at 4 pm ET today confirming that it purchased the 22 patents from AST, but offering no additional information or details -- not even a confirmation that the patents "read on Linux." "To date, the Trust (AST) has invested $40 million in patent purchases over its 30 months of operations," the release said.

The original WSJ story leaves me with more than a few questions:

• Lately, Linux vendors have been steeling themselves against the possibility of Microsoft pursuing them for alleged patent violations. But in this case -- since Microsoft sold these patents -- who were the OIN members worried about? Which trolls were lurking?
• The Journal cites an OIN official claiming that Microsoft presented the graphics patents as being "Linux-related" when it auctioned them off earlier this year. (Microsoft did not confirm this characterization in the Journal's story.) If the patents really are Linux-related, I'd think Microsoft would have wanted to hold onto them, to give the company a leg up against its Linux competitors, rather than sell the patents off, claiming they weren't germane to Microsoft's core business.
• What, exactly, do these 22 patents cover? Back in January 2002, The Register reported that Microsoft paid $63 million for SGI's graphics patent portfolio. In July of that same year, Microsoft was rattling the patent sabers over OpenGL. Microsoft officials said they had "possible claims" on a technology called vertex programming, a technology that controls 3D effects such as lighting. A ZDNet story from that time noted that "The claims caused some consternation within the OpenGL Architectural Review Board (ARB), which governs the specification."

Anything else about this transaction of interest to you (in case I do get to talk to any of the parties in question later today)?