1. Section 102(a)'s 'known or used' determination (prior art)
One of the biggest changes made by AIA is the switch from "first inventor to file" to "first to invent." As Dennis Crouch points out on the PatentlyO site, "Prior art is now keyed to the effective filing date of the application-in-question and – except for grace period and derivation purposes – dates of conception and reduction to practice are no longer relevant . . . . The fact that someone else invented your idea first (or something similar to your idea) is irrelevant except in the limited case of a derivation proceeding. Rather, what matters in the general case is whether that other party created prior art." Another important change is that on-sale and public-use rules apply not only in the U.S. but anywhere in the world.
In Finjan, Inc. v. Symantec Corp., the U.S. District Court for the Delaware District addressed the requirements for determining prior art:
"To determine whether an invention is patentable over the prior art, 'a court must ask whether the improvement is more than the predictable use of prior elements according to their established functions.' KSR Int'l Co. v. Teleflex, Inc. (2007) 550 U.S. 398, 417, 419, [127 S.Ct. 1727, 167 L.Ed. 2d 705]. In this assessment, 'the invention must be considered as a whole without the benefit of hindsight, and the claims must be considered in their entirety.' Rockwell Int'l Corp. v. United States (1998) 147 F.3d 1358, 1364.) (citing W.L. Gore & Assocs. v. Garlock, Inc. (1983) 721 F.2d 1540, 1551); Medtronic, Inc. v. Cardiac Pacemakers, Inc. (1983) 721 F.2d 1563, 1567. Invalidity by 'anticipation requires that the four corners of a single prior art document describe every element of the claimed invention, either expressly or impliedly, such that a person of ordinary skill in the art could practice the invention without undue experimentation.' Advanced Display Sys., Inc. v. Kent State Univ. (2000) 212 F.3d 1272, 1282."
"When challenging the validity of a patent for obviousness based on a combination of prior art references, the challenger bears the burden of proving, by clear and convincing evidence, that one of ordinary skill in the art would have had reason to attempt to make the combination and would have had a reasonable expectation of success in doing so. PharmaStem Therapeutics, Inc. v. ViaCell, Inc. (2007) 491 F.3d 1342, 1360. A defendant must prove invalidity by clear and convincing evidence and the ultimate burden of persuasion never shifts to the plaintiff. See Pfizer, Inc. v. Teva Pharms. U.S.A., Inc. (2012) 882 F. Supp. 2d 643, 700." (Finjan, Inc. v. Symantec Corp., 2013 U.S. Dist. LEXIS 134030 (D. Del. Sept. 19, 2013 at 10-12.)
The Finjan court thus laid out the requirements for a prior-art defense to a patent-infringement claim: 1) predictable use of prior elements when considering the invention as a whole at the time the patent was filed, 2) existence of a prior-art document that describes explicitly or implicitly every element of the invention in a way that a person with ordinary skill in the art could "practice without undue experimentation," and 3) proof via clear and convincing evidence that one practiced in the art would have reason to "attempt the combination" and "reasonable expectation of success." In the software context, these requirements place an onerous burden on a party challenging a software-related patent.
Research entails hundreds -- perhaps thousands -- of failures before achieving success. Program development in particular is often a matter of stumbling through hundreds of combinations of thousands of code snippets until tripping over almost serendipitously the long string that achieves the development project's goal. In this sense, programming is as much an art as it is a science: programmers often feel their way through the code as much as they purposefully devise it.
In the patent-challenger's favor is the unambiguousness of the actual software code. In Finjan, Symantec was able to meet the clear-and-convincing standard of proof that Finjan's product was available prior to the date of Finjan's patent application. Symantec demonstrated that the product was " known, used, sold, and on sale in the United States" prior to the effective patent date. (Id. at 21.) Whether a person with ordinary skill in the art could have combined the elements was a question the court left to the jury, which found in Symantec's favor. Simply put, Finjan's expert testified such a person could not have combined the elements in the same way, and Symantec's expert testified that a person skilled in the art could have done so. The jury found Symantec's expert more credible.
2. Section 102(b)'s "on sale" and "disclosure" determinations