The Federal Circuit has affirmed the Patent Trial and Appeal Board’s (PTAB or Board) invalidation of Shockwave’s angioplasty balloon catheter claims on the basis of obviousness.
The case is Shockwave Medical, Inc. v. Cardiovascular Systems, Inc.
As the court explained,
Shockwave owns the ’371 patent, entitled “Shockwave Balloon Catheter System,” which is directed to the treatment of atherosclerosis through intravascular lithotripsy (“IVL”). Atherosclerosis is a common health condition characterized by the buildup of fatty deposits in blood vessels. These deposits may gradually harden into calcified atherosclerotic plaque and restrict blood flow, causing coronary artery disease or vascular disease. Balloon angioplasty is a well-known method of treating atherosclerosis and involves guiding a balloon catheter to the location of the blood vessel that contains the calcified plaque buildup: Once in place, the balloon is inflated, widening the blood vessel and increasing blood flow. A typical balloon catheter is the over-the-wire balloon catheter, which consists of a hollow carrier (called a lumen), which is inserted over a wire to guide the balloon catheter to the correct position.
The court also explained that lithotripsy is a well-known technique used in the treatment of kidney stones that involves sending shockwaves—a form of high-intensity sonic wave—directly toward kidney stones. The shockwaves break up larger stones into smaller stones, allowing them to pass through the urinary system.
The ’371 patent applies this technique to breaking up calcified plaque deposits in the context of treating atherosclerosis. The claimed device uses a typical over-the-wire angioplasty balloon catheter and adds electrodes and a pulse generator.
Cardiovascular Systems, Inc. (CSI) filed an IPR petition challenging all 17 claims of the ’371 patent as obvious over various prior art combinations.
As the court explained,
CSI argued that it would have been obvious to an ordinarily skilled artisan to modify Levy with the well-known angioplasty balloon catheter disclosed by the applicant admitted prior art (“AAPA”). Its proffered prior art combinations (which are the subject of the appeal and cross-appeal) involved “Levy as modified by AAPA” in combination with other prior art references.
As the court explained,
AAPA is art referenced in a patent application that is admitted by the applicant to be prior art. We recently approved the role of AAPA as evidence of general background knowledge of an ordinarily skilled artisan…
However, said the court, AAPA cannot be the “basis” of a ground in an IPR petition.
Because the Board hadn’t addressed the issue whether the AAPA formed the basis of the petition, the court remanded to allow the Board to address this issue.
On remand, the Board held that AAPA does not form the basis of a ground in violation of § 311(b) if the ground relies on the AAPA “in combination with” permissible prior art patents or printed publications.
Based on this interpretation, the Board found that the ground relied upon by the petitioner was compliant with § 311(b).
Under 35 U.S.C. § 311(b),
A petitioner in an inter partes review may request to cancel as unpatentable 1 or more claims of a patent only on a ground that could be raised under section 102 or 103 and only on the basis of prior art consisting of patents or printed publications.
On a second appeal, the court reversed, since the IPR petitioner had expressly labeled the AAPA as part of its “basis” for its obviousness ground.
In 2023, the PTAB issued its Final Decision on Rehearing, relying on AAPA only as evidence of the background knowledge in the art as to typical over-the-wire balloon catheters and again determining that claims 1–4 and 6–17 had been shown to be unpatentable as obvious but that claim 5 had not.
The parties cross-appealed.
The Federal Circuit noted that this case was different from a previous case in which the petitioner expressly labeled AAPA as the “basis” for its challenge.
Here, said the court,
CSI used AAPA only to show, as the ’371 patent itself acknowledged, that the over-the-wire angioplasty balloon catheter was well known in the prior art and that this general background knowledge satisfied the ’371 patent’s claim limitations relating to an over-the-wire configuration.
Said the court,
We have not previously decided whether AAPA improperly forms the basis for a petition when it is used to show that a claim limitation (characterized by the patent as not disclosed in the prior art) would have been obvious over the prior art. That is not the case here, where CSI properly relied on general background knowledge to supply missing claim limitations (which Shockwave does not argue were novel to the invention) and used AAPA as evidence of that general background knowledge. The IPR petition did not violate § 311(b).
The court subsequently affirmed the Board’s determinations as to claims 1–4 and 6–17 in Shockwave’s direct appeal and reversed the Board’s determination as to claim 5 in CSI’s cross-appeal.
Just like the haiku above, we like to keep our posts short and sweet. Hopefully, you found this bite-sized information helpful. If you would like more information, please do not hesitate to contact us here: https://aeonlaw.com/contact-us/.
