BASICS: “Invention date” is important primarily in two contexts: (1) a patent applicant’s “invention date” may antedate certain prior art (e.g., Sec. 102(a) or 102(e) references), e.g., NFC Tech. (Fed. Cir. 09/20/17) (rev’g PTAB decision that patent owner had failed its burden to prove invention date earlier than Sec. 102(e) reference); Perfect Surgical (Fed. Cir. 11/15/16) (2-1) (vacating PTAB finding that applicant lacked reasonable diligence toward constructive reduction to practice), and (2) another’s invention as of a particular “invention date” may qualify as prior art, under Sec. 102(g). “Invention date” is the date of reduction to practice of the claimed invention, extended as far back toward conception as continuous diligence can take it: “A person shall be entitled to a patent unless– … before such person’s invention thereof, the invention was made in this country by another inventor who had not abandoned, suppressed, or concealed it. In determining priority of invention under this subsection, there shall be considered not only the respective dates of conception and reduction to practice of the invention, but also the reasonable diligence of one who was first to conceive and last to reduce to practice, from a time prior to conception by the other.” 35 U.S.C. § 102(g) (pre-AIA); Tyco Healthcare (Fed. Cir. 12/04/14) (aff’g finding of prior invention based on drawings and building a prototype coupled with diligence to constructive reduction to practice). “To antedate (or establish priority) of an invention, a party must show either an earlier reduction to practice, or an earlier conception followed by a diligent reduction to practice.” Purdue Pharma (Fed. Cir. 02/06/01). Mere delay is not enough to prove suppression or concealment. Flex-Rest (Fed. Cir. 07/13/06). Excessive delay may bar first inventor from relying on early reduction to practice but not from relying on later, resumed activity antedating second inventor’s work. Paulik (Fed. Cir. 04/22/85) (en banc). Patent owner has burden of production to prove date of invention before putative prior art. Allergan (Fed. Cir. 06/10/14) (documents did not corroborate oral testimony of conception date). “Priority, conception, and reduction to practice are questions of law which are based on subsidiary factual findings.” E.I. duPont (Fed. Cir. 04/17/19) (aff’g jury verdict that inventors’ invention date antedates public use, despite lack of independent corroborating evidence for exact claim-recited range); Alexsam (Fed. Cir. 06/16/15) (non-precedential) (rev’g jury verdict of no Sec. 102(g) anticipation; prior art reduced to practice before patent filing date and patent owner did not meet burden of production to show earlier invention).
AIA: Changes everything on this subject for patents governed by it. (See following row.)
To Antedate A Presumptive Prior Art Reference, The Inventive Acts May Have Been In Any WTO Country: To antedate a Sec. 102(a) or Sec. 102(e) presumptive prior art reference, the inventor(s) of the challenged patent can show prior invention in the U.S., or in a NAFTA country (after December 8, 1993), or in a WTO country (after Jan. 1, 1996), per Sec. 104 (pre-AIA); See MPEP 715.
Date Of Invention Measured Against As-Construed Claimed Invention: Intellectual Ventures (Motorola) (Fed. Cir. 05/31/17) (non-precedential) (vacating PTAB unpatentability decision based on reference patent owner tried to predate by showing an earlier date of invention; PTAB erred by requiring patent owner corroboration of a feature that PTAB refused to include in its claim construction).
Conception Is Definite And Permanent Idea Of Complete And Operative Invention: “‘The conception of the invention consists in the complete performance of the mental part of the inventive act. All that remains to be accomplished, in order to perfect the act or instrument, belongs to the department of construction, not invention. It is therefore the formation, in the mind of the inventor, of a definite and permanent idea of the complete and operative invention, as it is thereafter to be applied in practice, that constitutes an available conception, within the meaning of the patent law.’” Gunter (CCPA 04/06/78) (aff’g conception and priority proven in interference). “Conception is the formation, in the mind of the inventor, of ‘a definite and permanent idea of the complete and operative invention. The idea must be ‘so clearly defined in the inventor’s mind that only ordinary skill would be necessary to reduce the invention to practice, without extensive research or experimentation.’” Stamps.com (Fed. Cir. 06/15/11) (non-precedential) (aff’g Summ. J., patentee failed to sufficiently corroborate alleged conception before Sec. 102(a) reference). “‘An idea is definite and permanent when the inventor has a specific, settled idea, a particular solution to the problem at hand, not just a general goal or research plan he hopes to pursue.’” Dawson (Fed. Cir. 03/25/13) (aff’g BPAI decision in interference that conception not proven); In re VerHoeff (Fed. Cir. 05/03/18) (omitted person was co-inventor because she proposed “a particular solution to the problem” which was “an essential feature of the invention not insignificant in quality or well-known in the art.”) “‘Conception requires that the inventor know how his ‘definite and permanent idea of the complete and operative invention . . . is hereafter to be applied in practice,’ i.e., the inventor must have ‘possess[ed] an operative method of making [the invention].’” Id. (citations omitted). AccordIn re Steed (Fed. Cir. 10/01/15) (aff’g PTAB ruling of no showing of conception before prior art’s date). “To establish prior invention, the party asserting it must prove that it appreciated what it had made. The prior inventor does not need to know everything about how or why its invention worked. Nor must it conceive of its invention using the same words as the patentee would later use to claim it.” Teva Pharm. (Fed. Cir. 12/01/11) (aff’g Summ. J. of invalidity under Sec. 102(g)(2)). Conception is a question of law based on subsidiary fact questions. NFC Tech. (Fed. Cir. 09/20/17).
Corroboration Is Needed To Prove Conception And Reduction To Practice: “‘[A]n inventor’s testimony, standing alone, is insufficient to prove conception—some form of corroboration must be shown.’” NFC Tech. (Fed. Cir. 09/20/17) (evidence as a whole corroborated inventor’s conception, particularly considering that events happened almost 20 years ago; rev’g PTAB finding to the contrary). SeeHigh Tech Amici Br. in Amgen v. Sanofi (S. Ct. 01/03/2023). “‘Conception must be proved by corroborating evidence which shows that the inventor disclosed to others his ‘completed thought expressed in such clear terms as to enable those skilled in the art’ to make the invention.’” Reg Synthetic (Fed. Cir. 11/08/16) (rev’g PTAB; patent owner proved earlier invention to pre-date asserted Sec. 102(e) reference; relying on emails with third party and rejecting hearsay objection); Coleman (Fed. Cir. 02/08/85) (aff’g BPAI finding that inventor’s conception testimony not sufficiently corroborated); Valencell (Fed. Cir. 09/26/19) (non-precedential) (aff’g PTAB finding evidence of exterior of prototype device did not corroborate internal claim elements of patent owner’s alleged prototype); Intellectual Ventures (Motorola) (Fed. Cir. 05/31/17) (non-precedential) (PTAB erred in imposing too strict a standard for evidence of corroboration; “focus must be whether the totality of the evidence makes the inventor’s testimony credible.” “Documents created shortly after the critical date and even undated documents may be relevant to corroborate an inventor’s testimony.”) The corroborating evidence must corroborate without depending on the inventor’s own testimony: “The evidence proffered by [inventor seeking to overcome a Sec. 102(e) reference filed 13 days earlier] is stuck in a catch-22 of corroboration: [patent owner] attempts to corroborate [inventor’s] testimony with the emails and the drawings, but the emails and drawings can only provide that corroboration with help from [inventor’s] testimony.” Apator (Fed. Cir. 04/17/18) (aff’g PTAB anticipation); Kolcraft (Fed. Cir. 07/02/19) (aff’g PTAB obviousness; inventors’ testimony to try to antedate reference not corroborated by evidence that did not depend on the inventor’s testimony). While inventor’s testimony showing reduction to practice must be corroborated under a “rule of reason analysis,” “corroborating evidence need not disclose each and every aspect of the claimed invention.” Raytheon (Fed. Cir. 04/02/18) (non-precedential) (aff’g PTAB obviousness, upholding finding that patent owner did not show reduction to practice before asserted reference’s priority date where allegedly corroborating evidence showed that one element was yet to be constructed).
Actual Reduction To Practice: “In order to establish an actual reduction to practice, the inventor must prove that: (1) he constructed an embodiment or performed a process that met all the limitations of the [claim]; and (2) he determined that the invention would work for its intended purpose.” Taskett (Fed. Cir. 09/26/03) (does not require “viable commercial embodiment”); Minerva (Fed. Cir. 02/15/23) (aff’g Summ. J. of public use invalidity; surgical device reduced to practice by working prototypes even if not ready for use on live humans (as claims not so limited) or ready for FDA approval); Cooper (Fed. Cir. 09/01/98) (same, for interference count); Alexsam (Fed. Cir. 06/16/15) (non-precedential) (rev’g jury verdict of no Sec. 102(g) anticipation, based on successful, non-public pilot testing). The intended purpose need not be explicitly included in the claim. Barry (Fed. Cir. 01/24/19) (2-1) (aff’g jury verdict of no public use bar; substantial evidence supports that doctor did not know invention would work for intended purpose, identified in claim’s preamble and patent’s specification, until had follow up with all three patients on which performed surgeries, “who fairly reflected the real-world range of application of the inventive method,” and therefore neither ready for patenting nor in public use. Collecting cases where “intended purpose” not recited in claims.); Streck (Fed. Cir. 10/16/11) (interference context) (seeStreck (Fed. Cir. 01/10/12) (companion infringement suit)). Sufficiency of testing to show an invention works for its intended purpose is question of fact. Id.; Ideal Innovations (Fed. Cir. 12/03/21) (non-precedential) (where existence of license turned on whether actual reduction to practice occurred before or during term of contract, and only armor not full vehicle with armor was tested before the contract, rev’g CFC grant of Summ. J. that there was no pre-contract actual reduction to practice, finding a disputed issue of fact “whether a POSA would have known, based on [certain testing], that the invention would work for its intended purpose.” Testing need show “only utility beyond a probability of failure.”). For another’s reduction to practice to inure to benefit of inventor requires only that the inventor authorized that reduction to practice, not that the inventor requested it or even knew of it. Solvay II (Fed. Cir. 02/12/14) (2-1). Embodiment must include all elements of a claim not just an equivalent element. Alexsam (Fed. Cir. 06/16/15) (non-precedential). “The inventor must also have ‘contemporaneous recognition and appreciation of the invention represented’ by the claims.” Purdue Pharma (Fed. Cir. 02/06/01) (aff’g finding of reduction to practice predating asserted art, in aff’g preliminary injunction).
Diligence: “A patent owner need not prove the inventor continuously exercised reasonable diligence throughout the critical period; it must show there was reasonably continuous ” Perfect Surgical (Fed. Cir. 11/15/16) (2-1) (vacating PTAB finding that applicant (attempting to antedate a reference) lacked reasonable diligence over about a 3-month period toward constructive reduction to practice: “the point of the diligence analysis is not to scour the patent owner’s corroborating evidence in search of intervals of time where the patent owner has failed to substantiate some sort of activity. It is to assure that, in light of the evidence as a whole, ‘the invention was not abandoned or unreasonably delayed.’”). “The purpose of the diligence requirement is to show that the invention was not abandoned or set aside.” ATI Tech. (Fed. Cir. 04/11/19) (rev’g PTAB finding that patent owner had failed to show diligence, based on 1,300 pages of documentary evidence that up to 100 employees were working on the project every day; “diligence is not negated if the inventor works on improvements and evaluates alternatives while developing an invention.”) SeeBrown (Fed. Cir. 02/02/06) (discussion of evidence needed to prove diligence); Garmin (PTAB (IPR) 11/13/13) (insufficient showing of reasonably continuous activity to show diligence); In re Enhanced Security (Fed. Cir. 01/13/14) (aff’g Board finding of insufficient showing of diligence over four-month period it took to file patent application). “Lack of diligence cannot be inferred from putting the invention into someone else’s hands for needed testing and awaiting test results for a short period commensurate with the testing need, at least where oversight was diligent.” Arctic Cat (Fed. Cir. 03/26/19) (rev’g PTAB finding that inventor had failed to antedate prior art reference).
In This Country: Under Sec. 102(g)(2), where invention made abroad, date invention was disclosed in U.S. is the date of conception in this country. Disclosure need not be in writing, but must be “specific enough to encompass the ‘complete and operative’ invention.” Amkor Tech. (Fed. Cir. 08/22/12) (rev’g ITC finding that claims invalid under Sec. 102(g)(2)).
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