Source: https://ipspotlight.com/2012/12/06/i-invented-that-challenging-inventorship-to-a-u-s-patent/
Timestamp: 2019-04-23 23:56:52+00:00

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A recent court decision sheds light on a not-often-used section of the Patent Act: Section 256, which provides a private right of action for correcting inventorship of an issued patent.
In Pei-Herng Hor v. Ching-Wu “Paul” Chu (No. 2011-1540, Nov. 14, 2012), two plaintiffs filed suit against a patent holder and asserted that they were co-inventors whom the defendant should have named on two patents. The patents were filed in 1986 and 1987 but did not grant until 2006 and 2010. The plaintiffs filed their suit in 2010, and in its defense the patent holder argued that the claims were barred by laches since the plaintiffs should have known of the claims when the patents were filed in the 1980s.
The Court noted that “for inventorship claims under § 256, a delay of six years after a claim accrues creates a rebuttable presumption of laches.” However, the Court found that the laches clock cannot start until the patent grants. Thus, despite a potential delay of over 20 years, the Court permitted the plaintiffs’ claims to proceed.
The failure to name a co-inventor most be established by clear and convincing evidence. C. R. Bard, Inc. v. M3 Systems, Inc., 157 F.3d 1340, 1352 (Fed. Cir. 1998). This can be a high hurdle for cases where the documentary evidence is thin.
Correction of inventorship requires collaboration with the named inventor. A person claiming to have independently invented the invention cannot bring suit under § 256. See, e.g., Ethicon, Inc. v. United States Surgical Corp., 135 F.3d 1456, 1461 (Fed. Cir. 1998).
The inventor must have contributed to the conception of the invention, not merely its reduction to practice. Coleman v. Dines, 754 F.2d 353, 359 (Fed. Cir. 1985).
The challenger’s contribution must be more than a de minimis amount. “[A] joint inventor must contribute in some significant manner to the conception of the invention.” Fina Oil and Chemical Co. v. Ewen, 123 F.3d 1466, 1473 (Fed. Cir. 1977).
From Sept. 26, 2012 the phrase “and such error arose without any deceptive intention on his part” has been removed from section 116.
You are correct. Thanks for pointing that out!

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