May 31, 2016
In Enfish v. Microsoft et al, the CAFC (2015-1244) continues to split hairs about software as patentable subject matter under §101. Enfish's 6,151,604 and 6,163,775 claim a "self-referential" database, where the database is a single table with "the table's columns defined by rows." (The garden-variety relational database uses multiple tables with references between tables.)
The district court found claiming a self-referential database to be prima facie unpatentable for being abstract ("the concept of organizing information using tabular formats"). But the CAFC reversed, seeing the claims as "directed to a specific improvement to the way computers operate." Because "the claims are directed to a specific implementation of a solution to a problem in the software arts," self-referencing was considered not to be abstract to the appeals court, even though self-referencing is most certainly an abstract idea.
Any logician would have a seizure trying to ferret a rational rule base under current case law for software standing up to §101 when it does not direct physical activity. What most certainly cannot be patented is anything that involves financial or business practices, no matter how specific or novel. The CAFC found in First Choice Loan Services v. Mortgate Grader (2016) that "computational methods which can be performed entirely in the human mind" are not patentable. Beyond the court-sanctioned vagary of being "specific" in this instance, how fiddling with a self-referential table is something other than a mental method, and so passes muster under §101, is inscrutable.