Teleflex Catheter Tech Patents Upheld by Split CAFC

“Although the patents themselves are the most important and, indeed, most persuasive evidence of the patents’ intended purpose, we find it is appropriate to consider extrinsic evidence, particularly when it does not contradict the patents themselves.”- CAFC

CAFCThe U.S. Court of Appeals for the Federal Circuit (CAFC) ruled in a precedential decision today that Medtronic, Inc. failed to show the challenged claims of five patents covering catheter technology unpatentable. The CAFC specifically upheld the Patent Trial and Appeal Board’s (PTAB’s) finding that the primary prior art reference cited by Medtronic did not qualify as prior art under pre-America Invents Act (AIA) first-to-invent provisions. Judge Dyk dissented, arguing that the prior art reference had been shown to qualify as prior art, and thus could support a determination of anticipation or obviousness.

The patents in question are U.S. Patents 8,048,032, RE45,380, RE45,776, RE45,760, and RE47,379. All of the patents descend from a common application filed on May 3, 2006, and are now owned by Teleflex Innovations S.À.R.L. The inventions are specifically directed to “guide extension catheters that use a tapered inner catheter that runs over a standard coronary guidewire to reduce the likelihood that a guide catheter will dislodge from the coronary artery’s opening,” according to the CAFC.

Reduction to Practice

Teleflex’s predecessor, Vascular Solutions, Inc. (VSI), conceived of the technology in early 2005 and worked to develop it under the brand name, “GuideLiner”. A “Rapid Exchange” version of the GuideLiner technology practices the patents and entered the market in 2009. Medtronic filed 13 IPR petitions against Medtronic, five of which were consolidated in the present appeal. Teleflex argued in response to Medtronic’s petitions that the primary prior art reference asserted, U.S. Patent 7,736,355 (Itou), did not qualify as prior art because “the claimed inventions were (1) conceived prior to Itou’s filing date of September 23, 2005 (i.e., the critical date), and (2) were (a) actually reduced to practice before the critical date or (b) diligently pursued until their constructive reduction to practice through their effective filing in May 2006.”

Teleflex submitted numerous documents and declarations from inventors and others in support of its arguments. The PTAB ultimately found that the evidence supported Teleflex’s position; in particular, the Board said the inventions were “(1) conceived no later than August 2005, i.e., before the critical date, and (2) either (a) actually reduced to practice for their intended purpose in April and July 2005, prior to the critical date, or (b) diligently worked on toward constructive reduction to practice on May 3, 2006, the challenged patents’ effective filing date.” The PTAB also found that the purpose of the inventions was to provide improved backup support for the guide catheter, rather than to provide backup support necessary for accessing and crossing tough or chronic occlusions, as Medtronic contended was the additional intended purpose.

Addressing the Prior Art

In its discussion, the CAFC explained that to show an actual reduction to practice before the critical date, Teleflex must have demonstrated that “(1) [the inventors] constructed an embodiment or performed a process that met all the limitations of the [claimed invention]; and (2) [the inventors] determined that the invention would work for its intended purpose.”

Despite the burden of proving invalidity resting with petitioners in IPR proceedings, “when a patent owner attempts to antedate an asserted prior art reference, the patent owner takes on a temporary burden of production…. Once that burden is met, the burden shifts back to the petitioner,” the court explained. On appeal, Medtronic argued that 1) “the Board erred in identifying the intended purpose of the claimed inventions”; 2) “even if the Board’s finding of the intended purpose was correct, the Board erred in not requiring comparative testing to demonstrate that the invention worked for that purpose”; and 3) “the Board erred in relying solely on uncorroborated inventor testimony as evidence of actual reduction to practice.”

On the first argument, the CAFC rejected Medtronic’s claims that the Board’s reliance on extrinsic evidence to determine the intended purpose of the inventions was improper, arguing the proper sources were the patents’ claims and specifications. But the CAFC said “although the patents themselves are the most important and, indeed, most persuasive evidence of the patents’ intended purpose, we find it is appropriate to consider extrinsic evidence, particularly when it does not contradict the patents themselves.” Based on the evidence it considered, the CAFC said it found Medtronic’s proposed intended purpose to be overly narrow.

As to Medtronic’s second argument, the CAFC said that, while Medtronic’s argument on this point was not forfeited, as Teleflex proposed, the testing evidence presented was sufficient to show the invention worked for its intended purpose. And on the third point, the CAFC said it found the inventors’ testimony of actual reduction to practice sufficiently corroborated by documentary evidence and non-inventory testimony. While the court conceded that Medtronic’s assertion that hat some of the evidence was unclear as to whether it related to the over-the-wire GuideLiner or the rapid exchange GuideLiner was true, it said that the corroboration was still adequate when viewed in totality:

“That is true, and certain documents could only be connected to the rapid exchange prototype through inventor testimony, which carries little to no weight in the context of corroboration; one cannot corroborate oneself, after all. However, when viewing the pertinent evidence in its entirety, we still find the inventors’ story corroborated.”

Dyk Dissents

In dissent, Judge Dyk disagreed with the majority that Itou was not shown to be prior art. Dyk said this is because, under the pre-AIA statute, “Itou has an earlier filing date than that of the ’032 patent, and the evidence in this case fails to adequately corroborate inventor testimony that the rapid exchange (‘RX’) GuideLiner invention had been reduced to practice before Itou’s
filing date of September 23, 2005.” Dyk’s specific argument had to do with the lack of corroboration for evidence of testing of the RX GuideLiner prototypes before the critical date had shown them to work for their intended purpose.

Dyk rejected the majority’s contention that “finding the evidence insufficient here would impose an ‘impossible standard of ‘independence’ on corroborative evidence by requiring that every point of reduction to practice be corroborated by evidence having a source totally independent of the inventor.’” He noted that “Teleflex produced essentially no internal documents corroborating any testing that Vascular Solutions was doing with the RX GuideLiner prototypes in the critical period in 2005” and claimed “common sense, and Teleflex’s own testimony, suggest that these documents would exist if testing had occurred.” While Teleflex argued that the intrinsic evidence had been destroyed, Dyk concluded that “[a] rule that favors the retention of relevant documents does not create an ‘impossible standard’ for inventors seeking to enforce a patent for a claimed invention.”

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Author: billperry 


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Join the Discussion

3 comments so far.

  • [Avatar for Pro Say]
    Pro Say
    May 25, 2023 07:20 pm

    Thanks for your thoughts David.

    So . . . would be interesting were Medtronic to purchase ‘355 and file an interference . . . ‘specially were the case to end up at the CAFC . . . with a new panel . . . that included Judge Dyk.

    Wonder whether such a thing has ever been attempted before . . .

  • [Avatar for David Lewis]
    David Lewis
    May 25, 2023 12:40 pm

    I would think that, as long as the patent being asserted claims a different invention than 7,736,355 the decision says essentially nothing about the validity of patent 7,736,355 , because the inventor’s reduction to practice was presumably not public and is therefore not prior art against patent # 7,736,355. However, were patent 7,736,355 to claim the same invention as one of the patents being asserted, then there may potentially be an interference, which could potentially result in either the patent being asserted or 7,736,355 being invalid. Presumably, patent 7,736,355 does not claim the same invention as the asserted patents or the case or at least the decision would have been considerably different.

  • [Avatar for Pro Say]
    Pro Say
    May 24, 2023 04:39 pm

    What, if any, effect(s) does this precedential decision have on 7,736,355 (e.g., (it’s claim/s) rendered anticipated and/or obvious)?

    Inquiring minds (should) want to know.