Proving Invalidity Based on Prior Invention Under 35 U.S.C. 102(g)(2)
Successful patent invalidity challenges asserting prior invention under § 102(g)(2) are rare, which makes Judge Smith’s recent award of summary judgment on that basis even more noteworthy. In her latest opinion in The Fox Group, Inc. v. Cree, Inc., Case No. 2:10CV314, 2011 U.S. Dist. LEXIS 87231 (E.D.Va. Aug. 8, 2011), found here, Judge Smith sets out a helpful roadmap for an accused infringer pursuing a § 102(g)(2) invalidity claim.
Proof of the Defense
Under §102(g)(2), a patent is invalid if the invention has been made by another inventor who had not abandoned suppressed or concealed it.
The Court noted two ways to prove prior invention: (1) by reducing the invention to practice first or (2) by being the first to conceive the invention and then exercising reasonable diligence in reducing it to practice.
Cree asserted prior invention by reduction to practice, which requires:
- construction of an embodiment that met all the limitations of a patent’s claims; and
- a determination that the invention would work for its intended purpose
Once actual reduction to practice is established, the burden shifts to the patentee to show that the prior inventor abandoned, suppressed or concealed the invention.
Reduction to Practice
Fox challenged whether Cree met the second prong of the reduction to practice test – “contemporaneous recognition and appreciation of the invention” – because Cree did not appreciate that its invention met the specific requirements of the patent’s claims.
On the contrary, Judge Smith held:
- A prior inventor is not required to show that he recognized the invention in the same terms as those in the patent’s claims.
- The invention is not the language of the claims but the subject matter thereby defined.
- Cree need only appreciate the novelty of its invention through (1) evidence of its subjective belief about its invention; and (2) objective evidence that corroborated that subjective belief.
Abandonment, Suppression or Concealment
Fox claimed that Cree’s delay in publicizing its invention constituted abandonment, suppression or concealment.
First, Fox argued that Cree did not publish any document which disclosed every element of the patent claims. Judge Smith quickly dismissed this claim because it was based on the requirements to prove anticipation under § 102(b) not prior invention under § 102(g)(2)
Second, Fox argued that Cree delayed nine years before it used its invention in a commercial product. Judge Smith rejected the position that a prior inventor must commercialize its product. Cree’s contemporaneous disclosure of the invention through a presentation and a paper at an international conference met any requirement of public disclosure.
Based on the findings of actual reduction to practice and absence of evidence of abandonment, suppression or concealment, Judge Smith entered judgment of invalidity and dismissed Cree’s claim for a declaration of non-infringement as moot.
