Opinion ID: 4540299
Heading Depth: 2
Heading Rank: 2

Heading: API Resource

Text: We review the Board’s claim construction de novo except for necessary subsidiary factual findings based on extrinsic evidence, which we review for substantial evidence. Acceleration Bay, LLC v. Activision Blizzard Inc., 908 F.3d 765, 769 (Fed. Cir. 2018). The Board construed the term “application programming interface (API) resource” in the operating clause as “a resource available through an API.” J.A. 8. Twilio argues the Board erred in its construction and obviousness analysis by not requiring that the API resource be identifiable by its URI. We do not agree. As an initial matter, the parties agreed that an API resource is a resource available through an API—the Board’s construction. Twilio, however, argued the construction should further include a requirement that the API resource be Case: 19-1842 Document: 59 Page: 7 Filed: 06/10/2020 TWILIO INC. v. TELESIGN CORPORATION 7 identifiable by its URI, for purposes of the operating limitation. The Board rejected Twilio’s argument “[b]ecause claim 1 separately recites a URI that identifies an API resource” in the receiving limitation. J.A. 8. We agree with the Board’s construction. Under the broadest reasonable interpretation standard, which applies here, nothing in the claim or specification limits the API resource as it is used in the operating limitation. 4 The ’376 patent’s specification supports the Board’s rejection of Twilio’s argument because the specification contemplates a broad scope of API resources—“any suitable commands or methods may be used to interface with an API resource.” ’376 patent at 8:65–9:1. Accordingly, we find no error in the Board’s construction.