Do you remember when Microsoft General Counsel Brad Smith and licensing chief Horacio Gutierrez asserted that FOSS infringes 235 Microsoft patents? Of course you do, for readers of this site that was a rhetorical question, and perhaps poor form for the beginning of an entry - sorry.

Anyhow, upon hearing these claims, many observers deduced that Microsoft must have performed a detailed analysis of their patent portfolio in regards to potential infringements in FOSS, and once again called on them to (finally) state with specificity precisely which spurious software patents they are alleging infringement on.

Amazingly, shortly after the vociferous reaction to Microsoft's vague threats, they backpedaled somewhat - explaining that no detailed analysis would take place, due to the prohibitive amount of paperwork that would be involved (not to mention those legitimate questions about patent quality).

So then, where does the number of 235 Microsoft patents come from, exactly? Some explanations state that Microsoft is (still) misinterpreting (or is it misrepresenting) the OSRM study from 2004 that found that Linux (the kernel) may potentially infringe on 283 issued but not-yet court validated patents. Ten percent of the patents found in the OSRM study were owned by Microsoft (about 28, statistically), perhaps in the last three years a dozen or so additional Microsoft patents that affect the kernel have been granted, which would jibe with Microsoft's latest tally of 42:

He says that the Linux kernel - the deepest layer of the free operating system, which interacts most directly with the computer hardware - violates 42 Microsoft patents. The Linux graphical user interfaces - essentially, the way design elements like menus and toolbars are set up - run afoul of another 65, he claims. The Open Office suite of programs, which is analogous to Microsoft Office, infringes 45 more. E-mail programs infringe 15, while other assorted FOSS programs allegedly transgress 68.

But, the OSRM study was only for the Linux kernel - where did Microsoft's OpenOffice.org, Email, GUI, and other patent statistics come from?