Prior Art

Prior Art counters an invention's novelty, a concept that concerns itself only with events that occur before the date of invention (the U.S., unlike various other countries, uses the date of invention to determine when an author conceived of an idea, rather than the the date the patent itself was filed). The novelty requirement dictates that a parent is invalid if, before the date of invention, the invention was (a) known or used by others in this country; or (b) patented or described in a printed publication anywhere in the world. See 35 U.S.C. §§ 102(a), (e,) (g).

Known by Others - Information regarding the prior art invention must be reasonably accessible to the public, or the invention must have been reduced to practice (actually created). National Tractor Pullers Ass'n v. Watkins, 205 U.S.P.Q. (BNA) 892 (N.D. Ill. 1980).

Used by Others - Must be non-secret use by others prior to the invention. Rosaire v. Baroid Sales, 218 F.2d 72 (5th Cir. 1955); W.L. Gore & Assoc. v. Garlock, Inc., 842 F.2d 1275 (Fed. Cir. 1988).

Abandoned Experiments - An abandoned, unsuccessful experiment cannot serve as prior art. Picard v. United Aircraft Corp., 128 F.2d 632 (2d Cir. 1942). However, an invention does not have to be sold to the public in order to transition from "uncompleted experiment" to "invention". Corona Cord Tire Co. v. Dovan Chemical Corp., 276 U.S. 358 (1928).

Patented - A U.S. patent disclosing an invention before the date of the filing of the application suffices as Prior Art. Alexander Milburn Co. v. Davis-Bournonville Co., 270 U.S. 390 (1926). Materials disclosed but not claimed in a patent is available as Prior Art (see 35 U.S.C. §§ 102(b)) if the patent is later granted or published; the date for the Prior Art is backdated to the original date the patent was filed.

There is a "statutory presumption" that a patent issued by the USPTO is valid, so any example of Prior Art must have its existence and relevancy established by "clear and convincing evidence" (in laymen's terms, you must have pretty convincing evidence that your example of prior art existed in one of the required forms before the invention at issue and that the example is similar enough that the invention is not novel in its own right, given the existence of the prior art).