"When testing is necessary to establish utility, there must be recognition and appreciation that the tests were successful for reduction to practice to occur." Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 594-95, 44 USPQ2d 1610, 1615 (Fed. Cir. 1997). The district court determined that the Genentech inventors did not understand the positive RRA test results to demonstrate the practical utility of the fusion protein.

See UMC Elecs. Co. v. United States, 816 F.2d 647, 652, 2 USPQ2d 1465, 1468 (Fed. Cir. 1987) ("[T]here cannot be a reduction to practice of the invention . . . without a physical embodiment which includes all limitations of the claim."); Estee Lauder Inc. v. L'Oreal S.A., 129 F.3d 588, 593, 44 USPQ2d 1610, 1614 (Fed. Cir. 1997) ("[A] reduction to practice does not occur until the inventor has determined that the invention will work for its intended purpose."). Depending on the character of the invention and the problem it solves, determining that the invention will work for its intended purpose may require testing.

Reduction to practice only occurs when the inventor determines "that the invention will work for its intended purpose." Estee Lauder Inc. v. L'Oreal, S.A. , 129 F.3d 588, 593 (Fed. Cir. 1997) ; see alsoScott v. Finney , 34 F.3d 1058, 1063 (Fed. Cir. 1994) ("Reduction to practice ... require[s] ... only a reasonable showing that the invention will work to overcome the problem that it addresses."). It is well-established that "conception and reduction to practice cannot be established nunc pro tunc.

Reduction to practice of a pharmaceutical compound means that the inventor "`actually prepared the composition and knew it would work.'" Estee Lauder, Inc. v. L'Oreal S.A., 129 F.3d 588, 592 (Fed. Cir. 1997) (quoting Hahn v. Wong, 892 F.2d 1028, 1032 (Fed. Cir. 1989)). As discussed above, precritical date experimental use of an invention evades the § 102(b) public use bar only when the experimentation represents a bona fide effort to perfect the invention or to ascertain whether it will answer its intended purpose.

Griffin argues that the count is not limited by the preamble "for diagnosing an increased risk of thrombosis or a genetic defect causing thrombosis" or by the "wherein" clauses directed to a correlation between the point mutation and decreased inactivation of Factor V by APC ( i.e., increased APC resistance) because those clauses merely state the inherent result of performing the manipulative steps. Griffin argues, relying on Reese v. Hurst, 661 F.2d 1222, 1228, 211 USPQ 936, 942 (CCPA 1981), that the sequencing gels themselves demonstrate that the inventors knew that the invention would work for its intended purpose, i.e., to identify a point mutation at an enzyme cleavage site in human Factor V protein, and that the Board erred in requiring more explicit recognition of the success of the invention as held in Estee Lauder Inc. v. L'Oreal S.A., 129 F.3d 588, 594-95, 44 USPQ2d 1610, 1615 (Fed. Cir. 1997).

"[W]hen testing is necessary to establish utility, there must be recognition and appreciation that the tests were successful for reduction to practice to occur." Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 594-95, 44 USPQ2d 1610, 1615 (Fed. Cir. 1997). The first prong of the reduction to practice test refers to "the interference count" because Cooper dealt with the appeal of an interference proceeding.

To prove actual reduction to practice, "an inventor must establish that he `actually prepared the composition and knew it would work.'" Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 592, 44 USPQ2d 1610, 1613 (Fed. Cir. 1997) (citations omitted); see also Mahurkar v. C.R. Bard, Inc., 79 F.3d 1572, 1577, 38 USPQ2d 1288, 1291 (Fed. Cir. 1996). The inventor must also have "contemporaneous recognition and appreciation of the invention represented" by the claims.

Because the record before the district court may include the evidence before the Board as well as evidence that was not before the Board, we have often described the district court proceeding as "a hybrid of an appeal and a trial de novo." Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 592, 44 U.S.P.Q.2d 1610, 1612 (Fed. Cir. 1997); see also General Instrument Corp. v. Scientific-Atlanta, Inc., 995 F.2d 209, 212, 27 U.S.P.Q.2d 1145, 1147 (Fed. Cir. 1993) ("[A] party may proceed to a district court for a hybrid appeal/trial de novo proceeding in which the PTO record is admitted on motion of either party, but it may be supplemented by further testimony. 35 U.S.C. § 146."); Case v. CPC Int'l, Inc., 730 F.2d 745, 752, 221 U.S.P.Q. 196, 202 (Fed. Cir. 1984) ("[A]n action under 35 U.S.C. § 146 has the hybrid nature of an appeal and a trial de novo.").

Reduction to practice is a legal issue based on underlying factual determinations. Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 592 (Fed. Cir. 1997). "To demonstrate an actual reduction to practice, the [patentee] must have: (1) constructed an embodiment or performed a process that met all the limitations of the claim and (2) determined that the invention would work for its intended purpose."

However, while the conclusion expressed in the documents was that heating for 60 minutes at 110°C “will give” more than a 7 log reduction, PTX 1034 clearly demonstrates that the samples were not actually heated at that time and temperature. PTX 1034 at 1335866–67; cf. Purdue Pharma, 237 F.3d at 1365 (“To prove actual reduction to practice, ‘an inventor must establish that he actually prepared the composition....’ ” (citing Estee Lauder Inc. v. L'Oreal, S.A., 129 F.3d 588, 592 (Fed.Cir.1997) )). Similarly, PTX 1527 provides no information regarding sterility of the heat-treated samples, and the testing conducted was not intended to even address sterility.