Prior Art - Usage in Litigation

Usage in Litigation

Arguments claiming prior art are used both in defending and attacking patent validity. In one U.S. case on the issue, the court said:

"One attacking the validity of a patent must present clear and convincing evidence establishing facts that lead to the legal conclusion of invalidity. 35 U.S.C. § 282. To establish invalidity under 35 U.S.C. § 103, certain factual predicates are required before the legal conclusion of obviousness or nonobviousness can be reached. The underlying factual determinations to be made are

(1) the scope and content of the prior art;

(2) the differences between the claimed invention and the prior art;

(3) the level of ordinary skill in the art; and

(4) objective evidence of non-obviousness, such as commercial success, long-felt but unsolved need, failure of others, copying, and unexpected results."

Graham v. John Deere Co., 383 U.S. 1, 17, 148 USPQ 459, 467 (1966).