My Patent Law class just finished up anticipation, which included a discussion of the on-sale bar issues in Pfaff v. Wells Electronics, 525 U.S. 55 (1998). Footnote 11 always makes me laugh (and sometimes even my students) given what was to come in the decade and a half after Pfaff in opinions such as KSR, eBay, Bilski, etc.:
Petitioner correctly argues that these provisions identify an interest in providing inventors with a definite standard for determining when a patent application must be filed. A rule that makes the timeliness of an application depend on the date when an invention is “substantially complete” seriously undermines the interest in certainty.11
11The Federal Circuit has developed a multifactor, “totality of the circumstances” test to determine the trigger for the on-sale bar. See, e. g., Micro Chemical, Inc. v. Great Plains Chemical Co., 103 F. 3d 1538, 1544 (1997) (stating that, in determining whether an invention is on sale for purposes of § 102(b), “`all of the circumstances surrounding the sale or offer to sell, including the stage of development of the invention and the nature of the invention, must be considered and weighed against the policies underlying section 102(b)’ “); see also UMC Electronics Co. v. United States, 816 F. 2d 647, 656 (1987) (stating the on-sale bar “does not lend itself to formulation into a set of precise requirements”). As the Federal Circuit itself has noted, this test “has been criticized as unnecessarily vague.” Seal-Flex, Inc. v. Athletic Track & Court Construction, 98 F. 3d 1318, 1323, n. 2 (1996).
525 U.S. at 65-66. Link to the Court’s opinion.