CAFC Affirms Denial of Preliminary Injunction for Boston Scientific in Spinal Ablation Patent Dispute Against Stryker

The U.S. Court of Appeals for the Federal Circuit (CAFC) issued a decision today in Boston Scientific Corp. v. Stryker Corporation, affirming the U.S. District Court for the District of New Jersey’s denial of a preliminary injunction that Boston Scientific Corp. and Relievant Medsystems, Inc. sought to block Stryker Corporation’s launch of its OptaBlate BVN spinal ablation device. The dispute centered on whether Stryker’s product induced infringement of claims 16 and 21 of the U.S. Patent No. 12,303,166.

The ‘166 patent covers methods for using a radiofrequency probe to ablate the basivertebral nerve, which transmits pain signals from damaged vertebral endplates in the spine. To reach the nerve, a physician must guide the probe through soft tissue, penetrate the vertebra’s cortical bone, and advance into its cancellous interior while avoiding the spinal cord. The asserted claims describe inserting an introducer through the pedicle of the vertebra such that its distal tip “reaches a cancellous portion of the vertebral body,” then delivering a curved instrument through the introducer to form a path to the target treatment zone where the nerve is ablated.

Stryker’s OptaBlate BVN device was designed to treat the same condition and received FDA clearance after Stryker used Boston Scientific’s previously approved product as a predicate device. Boston Scientific filed suit following Stryker’s announcement of clearance and moved for a preliminary injunction, arguing Stryker would induce physicians to infringe the ‘166 patent by instructing them to use the OptaBlate BVN’s “access cannula” consistent with the use of the claimed “introducer.” The district court denied the motion, “concluding that Boston Scientific had not demonstrated a likelihood of success on the merits or that an injunction would be in the public interest.”

Boston Scientific argued that the distal tip of the introducer needs only to approach or create access to the cancellous bone, without physically contacting it. Stryker maintained that “reaches” required the tip to physically touch the cancellous region. The district court adopted Stryker’s narrower reading, concluding the term required that the distal tip “‘touch[] or extend[] to’ the cancellous portion of the vertebral body.”

The CAFC found no abuse of discretion in the district court’s tentative construction, noting that neither side had presented substantive arguments on the term’s meaning below. As the district court described it, the parties “‘barely address[ed]’ the issue, did not ‘identify any intrinsic evidence,’ and their experts did not suggest that the term ‘reaches’has any special meaning in the art.” Standard dictionary sources offered multiple recognized meanings for “reach,” some supporting Boston Scientific’s reading and others supporting Stryker’s, and Boston Scientific itself acknowledged that “reaches” can include scenarios involving physical contact. On appeal, Boston Scientific raised additional intrinsic record arguments not presented below, but the CAFC concluded that, even accounting for those arguments, uncertainty regarding the claim language raised a substantial question of infringement. The court declined to resolve the ultimate proper construction at the preliminary injunction stage, noting that a claim construction hearing had been scheduled.

The court also found no clear error in the district court’s infringement analysis. Boston Scientific relied on Stryker training materials suggesting placement “just inside the vertebral body,” but the district court reasonably interpreted those as referring to the stylet rather than the access cannula. Other materials indicated the cannula could be “shy of the posterior wall,” and that the stylet tip should barely, if at all, enter the vertebral body. The CAFC found no abuse of discretion in concluding that the ambiguous evidence raised a substantial question of infringement.

Boston Scientific also relied on an internal Stryker document stating that the access cannula was “placed within the cancellous bone of the spine,” as well as a diagram in the OptaBlate BVN instructions for use depicting a tube within the cancellous region. Stryker’s expert argued that the illustrated tube was the curved conduit rather than the access cannula, and the district court found that reading was consistent with other disclosures in the same set of instructions. Taking the evidence individually and collectively, the CAFC agreed that Stryker had raised “a substantial question of noninfringement as to this issue.”

Before the district court, Boston Scientific raised the argument without elaboration in a footnote of its opening brief, citing a single paragraph in an expert declaration. The district court found the argument forfeited but addressed it on the merits regardless and concluded Boston Scientific had not established a likelihood of success. On appeal, the CAFC affirmed. The court explained the “doctrine of equivalents infringement is a ‘highly factual inquiry [that] rarely comes clear on a premature record,’” and a patentee must present “particularized testimony and linking argument” for a factfinder to distinguish infringing equivalents from non-infringing alternatives.

Stryker’s expert testified that varying the final placement of the access cannula was a substantial difference because the cannula’s distal tip determines the ultimate placement of the radiofrequency probe. The expert further noted that Boston Scientific’s own materials warned that positioning the cannula tip “too deep” would place the probe too anteriorly to reach the treatment site. Given the competing expert evidence and the limited presentation below, the CAFC concluded that Stryker had raised a substantial question of infringement on the doctrine of equivalents theory as well.

Ultimately, the Federal Circuit agreed that Boston Scientific had not shown a likelihood of success on the merits under any theory, and it affirmed the denial of the preliminary injunction and awarded costs to Stryker.