by Dennis Crouch
The case involving Medtronic and Teleflex centered on five patents related to a coaxial guide catheter used in interventional cardiology procedures. These patents, US Patents 8,048,032, RE45,380, RE45,776, RE45,760, and RE47,379, cover inventions devised to offer an “enhanced backup support” in contrast to using a guide catheter individually.
In an attempt to invalidate these patents, Medtronic launched a succession of Inter Partes Review (IPR) petitions. Despite the initial approval of the petitions, the Board eventually ruled in favor of Teleflex, the patent holder. The pivotal question on appeal was whether U.S. Patent 7,736,355 (“Itou”) could be regarded as prior art.
In a split decision, the Federal Circuit confirmed the Board’s decision, establishing that the first-to-invent law from before the America Invents Act (AIA) allowed Teleflex to antedate the prior art by demonstrating prior invention. The case underlines a situation where the transition to the AIA has resulted in the loss of certain rights for patent holders. Under the AIA’s provisions, Itou would have been considered prior art, therefore preventing Teleflex’s patenting. The also case stands out as Itou was clearly the first inventor, but this evidence was not taken into account due both to arcane pre-AIA rules and due to the IPR process focusing only on the published patent documents.
Teleflex’s patents claim a priority filing date of May 3, 2006, based on a purported conception date in early 2005. Itou’s priority application was filed in Japan in September 2004, and a year later, the US application was filed on September 23, 2005. Despite Itou pioneering the invention in Japan and filing the Japanese patent application prior to Teleflex’s invention, Teleflex arguably demonstrated an invention date that preceded Itou’s US filing date, which was critical for the court’s decision.
A crucial regulation in this context is pre-AIA 102(e), which introduces a form of ‘secret prior art’ for patent applications that are unpublished as of the patentee’s invention date. Under this regulation, a third party’s US or PCT patent application becomes prior art once published. However, the quirk of 102(e) as compared to pre-AIA 102(a) lies in the fact that these applications are treated as prior art from their filing date, not their publication date. An important subtlety is that a foreign patent filings, like Itou’s Japanese application, do not qualify as prior art under 102(e). In re Hilmer, 149 USPQ 480 (CCPA 1966).
Proving Prior Invention: The concept of ‘invention date’ is crucial in pre-AIA patent cases, and typically, this date is assumed to be the filing date of the patent application. The patentee can then furnish evidence to establish an earlier date of invention, which usually involves a sworn declaration from the inventor, corroborated by additional evidence. Perfect Surgical Techs., Inc. v. Olympus Am., Inc., 841 F.3d 1004 (Fed. Cir. 2016).
Both the Patent Trial and Appeal Board (PTAB) and the majority judges (Judge Lourie and Chief Judge Moore) concurred that Teleflex had provided adequate evidence to substantiate an earlier invention date. Judge Dyk, however, wrote in dissent.
It’s important to understand that the process of invention involves two steps – conception and reduction to practice. The majority and dissent agreed that Teleflex had provided evidence sufficient to proven both conception and the creation of a prototype before the critical date. However, reduction to practice also necessitates evidence demonstrating the suitability of the invention for its intended purpose. For complex inventions like the one in this case, the courts can require testing to establish this suitability prong. Steinberg v. Seitz, 517 F.2d 1359 (C.C.P.A. 1975). While the majority deemed the evidence of testing adequate, the dissent argued it was insufficient — with the debate focusing on the extent of corroboration required.
The majority observed, “[B]oth inventors Howard Root and Gregg Sutton testified regarding testing performed on a prototype of the claimed invention. These tests, although more qualitative than quantitative, were sufficient to confirm that the prototype would work for its intended purpose — providing increased backup support as compared with a guide catheter alone.” The judges concurred with the Board’s view that the tests did not require a direct comparison or a quantitative analysis to prove improvement in function. They also noted expert testimony suggesting “qualitative testing would have been sufficient.”
However, Judge Dyk, dissenting, questioned the lack of corroborative evidence supporting the prior testing. He cited to Cooper v. Goldfarb, 154 F.3d 1321 (Fed. Cir. 1998), to assert that “[i]n order to establish an actual reduction to practice, an inventor’s testimony must be corroborated by independent evidence.” Judge Dyk particularly concluded that every “inventive fact” should be corroborated with evidence beyond the inventors’ testimonies.
The corroborating evidence in this case included a sales presentation and two non-inventors’ testimonies. However, Judge Dyk believed that this evidence did not provide any information regarding proof of operation for the intended purpose. Specifically, there was “no specific description of what tests were performed or the results of the tests … [or] when the tests were performed and whether they were performed before the critical date.” Dissent.
The majority responded that not every detail of reduction-to-practice needs to be independently corroborated, advocating for a rule of reason. Despite agreeing with this general principle, Judge Dyk insisted that the lack of corroboratory evidence regarding testing for the intended use couldn’t be overlooked.
Judge Dyk, in his dissent, noted the lack of internal documents from Teleflex corroborating any testing during the crucial period in 2005. “Common sense, and Teleflex’s own testimony [showing record keeping in this area], suggest that these documents would exist if testing had occurred.” Dissent. He argued requiring such documents did not created an unreasonable standard for inventors seeking to enforce a patent claim. Judge Dyk’s dissent concludes that “I think that Itou has been shown to be prior art to the patents at issue and therefore could support a determination of anticipation or obviousness.”
However, the majority, led by Judge Lourie, disagreed with the dissent and upheld the PTAB’s decision in favor of Teleflex.
The attorneys for the appellants (Medtronic) were led by Tasha Bahal from Wilmer Cutler. Representing Teleflex were attorneys from Carlson Caspers, led by Derek Vandenburg.