Case: 19-1842     Document: 59    Page: 1   Filed: 06/10/2020




        NOTE: This disposition is nonprecedential.


   United States Court of Appeals
       for the Federal Circuit
                   ______________________

                      TWILIO INC.,
                        Appellant

                             v.

                TELESIGN CORPORATION,
                          Appellee
                   ______________________

                    2019-1842, 2019-1843
                   ______________________

     Appeals from the United States Patent and Trademark
 Office, Patent Trial and Appeal Board in Nos. IPR2017-
 01976, IPR2017-01977.
                  ______________________

                   Decided: June 10, 2020
                   ______________________

     SARAH J. GUSKE, Baker Botts LLP, San Francisco, CA,
 for appellant. Also represented by THOMAS B. CARTER, JR.,
 MICHELLE JACOBSON EBER, Houston, TX; LAUREN J.
 DREYER, Washington, DC.

     JESSE J. CAMACHO, Shook, Hardy & Bacon, LLP, Kan-
 sas City, MO, for appellee. Also represented by CHRISTINE
 A. GUASTELLO, MARY PEAL.
                  ______________________
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 2                       TWILIO INC.   v. TELESIGN CORPORATION



     Before MOORE, O’MALLEY, and HUGHES, Circuit Judges.
 MOORE, Circuit Judge.
     Twilio Inc. appeals the Patent Trial and Appeal Board’s
 inter partes review decisions holding claims 1–3, 5, 14, 16,
 17, and 19 of U.S. Patent No. 8,755,376 and claims 1–6, 9,
 and 13 of U.S. Patent No. 8,837,465 unpatentable as obvi-
 ous. Because the Board’s decisions were not erroneous and
 substantial evidence supports its findings, we affirm.
     The ’376 and ’465 patents relate to systems and meth-
 ods for processing telephony sessions that involve com-
 municating with an application server and accessing call
 router resources through an application programming in-
 terface (API). See ’376 patent at 1:60–66; ’465 patent at
 1:60–66. The Board held that the combination of U.S. Pa-
 tent No. 6,801,604 (Maes) and U.S. Patent Pub.
 No. 2003/0204756 (Ransom) rendered the challenged
 claims unpatentable as obvious. 1 Twilio appeals. We have
 jurisdiction under 28 U.S.C. § 1295(a)(4)(A).
                         DISCUSSION
     We review the Board’s factual determinations for sub-
 stantial evidence and its legal determinations de novo.
 Outdry Techs. Corp. v. Geox S.p.A., 859 F.3d 1364, 1367
 (Fed. Cir. 2017). Obviousness is a question of law, which is
 based on underlying factual findings. Id. We review the
 Board’s procedures for compliance with the Administrative
 Procedure Act (APA) de novo, and we must set aside Board



       1 Telesign’s petition challenging the ’376 patent
 claims included a third reference—U.S. Patent No.
 7,092,370 (Jiang)—to render dependent claims 5 and 17
 unpatentable as obvious. Telesign’s petitions also included
 other grounds. Twilio does not challenge the Board’s find-
 ings related to the Jiang reference or the other grounds on
 appeal.
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 TWILIO INC.   v. TELESIGN CORPORATION                       3



 decisions if they are “arbitrary, capricious, an abuse of dis-
 cretion, or otherwise not in accordance with law.” 5 U.S.C.
 § 706; EmeraChem Holdings, LLC v. Volkswagen Grp. of
 Am., Inc., 859 F.3d 1341, 1345 (Fed. Cir. 2017).
                        1. The ’376 Patent
     The ’376 patent relates to methods and systems that
 allow development of telephony applications using existing
 web development tools and resources. ’376 patent at 1:61–
 2:6. Specifically, the ’376 patent discloses a method of com-
 municating with an application server by initiating a te-
 lephony session, mapping a call to a Universal Resource
 Identifier (URI), sending a request to the server associated
 with the URI, processing the request, and receiving a re-
 sponse from the server. Id. at 2:57–65. Claim 1 of the ’376
 patent is illustrative: 2
     1. A method comprising:
     operating a telephony network and internet con-
     nected system cooperatively with a plurality of ap-
     plication programming Interface (API) resources,
     wherein operating the system comprises:
     initiating a telephony session,
     communicating with an application server to re-
     ceive an application response,
     converting the application response into executable
     operations to process the telephony session,
     creating at least one informational API resource;
     and




     2   Twilio’s challenges on appeal are limited to the lim-
 itations of claim 1. It does not separately challenge the
 Board’s findings related to any of the dependent claims.
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 4                       TWILIO INC.   v. TELESIGN CORPORATION



     exposing the plurality of API resources through a
     representational state transfer (REST) API that
     comprises:
     receiving a REST API request that specifies an API
     resource URI, and
     responding to the API request according to the re-
     quest and the specified resource URI.
 (emphasis added). The Board held claims 1–3, 5, 14, 16,
 17, and 19 of the ’376 patent unpatentable as obvious in
 view of the combination of Maes and Ransom. 3 Twilio ar-
 gues that the Board erred in its analysis of the responding
 limitation and in its construction of the term “API re-
 source.” It further challenges the Board’s motivation-to-
 combine finding. As discussed below, we hold that the
 Board did not err in its analysis and substantial evidence
 supports its findings.
                 A. The Responding Limitation
     The Board determined “that the combination of Maes
 and Ransom teaches responding to the REST API request
 according to the specified API resource URI.” J.A. 60. It
 found that Maes teaches that a “telephony gateway,
 TEL 20, responds to an API request that specifies an API
 resource, such as ‘MakeCall,’ ‘TransferCall,’ or ‘Record,’ by
 modifying the state of a telephony session according to the
 request and the specified resource, such as by initiating,
 transferring, or recording a call.” J.A. 59. The Board re-
 jected Twilio’s argument that those portions of Maes do not
 teach responding to an API request according to a specified



     3   As discussed above, the Board further relied on
 Jiang to supports its holding that dependent claims 5 and
 17 were obvious. Because Twilio only challenges the
 Board’s decisions as they relate to Maes and Ransom, we
 need not separately consider Jiang.
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 TWILIO INC.   v. TELESIGN CORPORATION                        5



 URI, finding that Maes teaches that the response may be
 to a single specified source. And the Board found that
 “Ransom teaches that an API request can be a REST API
 request that specifies an API resource URI.” J.A. 60.
     The Board’s findings are based on substantial evi-
 dence. Maes teaches a system with an “audio I/O subsys-
 tem (or ‘TEL’)” which “comprises a gateway (e.g., telephony
 platform) that connects voice audio streams from a network
 to the various speech engines.” J.A. 5214–15 at 8:51–52,
 9:5–7. It further teaches that the TEL component is “capa-
 ble of receiving the HTTP/SOAP requests” and is capable
 of responding to those requests. J.A. 5227 at 34:7–35:8.
 Moreover, Maes teaches, for example, “[i]f play and/or rec-
 ord are part of the request, number of bytes played/rec-
 orded, number of overruns/underruns, completion
 reason, . . . play/record start/stop time . . . are included in
 the response.” J.A. 5228 at 35:25–28. Thus, Maes teaches
 responding to API requests according to the request and
 the specified source. Ransom teaches that REST and
 SOAP “are two common web service models wherein HTTP
 is the underlying application protocol” and in the REST
 model, “the service being invoked is the URI being accessed
 through the web.” J.A. 5282 at [0163]. Therefore, as the
 Board found, a person of ordinary skill in the art would un-
 derstand that the HTTP/SOAP requests taught in Maes
 could instead be a REST API request with a specific URI,
 as taught in Ransom, resulting in the responding limita-
 tion.
     Twilio argues the Board improperly modified the
 grounds raised in Telesign’s petition by combining Ransom
 with Maes to teach the responding limitation when Tele-
 sign’s petition never referenced Ransom’s teachings with
 respect to that claim limitation. While it is true that it
 would “not be proper for the Board to deviate from the
 grounds in the petition and raise its own obviousness the-
 ory,” such is not the case here. Sirona Dental Sys. GmbH
 v. Institut Straumann AG, 892 F.3d 1349, 1356 (Fed. Cir.
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 6                      TWILIO INC.   v. TELESIGN CORPORATION



 2018). Telesign argued in its petition that the combination
 of Maes and Ransom teaches the claim limitations, includ-
 ing both the requesting and responding limitations. Tele-
 sign specifically argued that Maes teaches a REST API
 request that specifies a resource URI, and teaches a re-
 sponse to that same request. J.A. 6361–64. It further ar-
 gued that to the extent Maes does not teach a REST API
 request that specifies a URI, Ransom teaches that such a
 request was well known in the art. J.A. 6361–62. Accord-
 ingly, the Board found that Maes teaches responding to an
 API request and that Ransom teaches the API request can
 be a REST API request that specifies an API resource URI.
 J.A. 60. Telesign’s petition relies on Ransom to demon-
 strate that an API request can be a REST API request that
 specifies an API resource URI, which applies for both the
 requesting and responding limitations, and supports the
 Board’s findings related to the “responding” limitation. We
 hold therefore that the Board did not modify the grounds
 asserted in the petition, and substantial evidence supports
 the Board’s findings.
                        B. API Resource
     We review the Board’s claim construction de novo ex-
 cept for necessary subsidiary factual findings based on ex-
 trinsic 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 re-
 source 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 construc-
 tion. Twilio, however, argued the construction should fur-
 ther include a requirement that the API resource be
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 TWILIO INC.   v. TELESIGN CORPORATION                       7



 identifiable by its URI, for purposes of the operating limi-
 tation. The Board rejected Twilio’s argument “[b]ecause
 claim 1 separately recites a URI that identifies an API re-
 source” 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 re-
 sources—“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.
                     C. Motivation to Combine
      The Board found that a person of ordinary skill in the
 art would have been motivated to combine the teachings of
 Maes and Ransom. J.A. 66–71. Twilio argues that the
 Board’s finding that the references could be combined
 lacked any explanation for why a person of ordinary skill
 in the art would combine them. We do not agree. As the
 Board explained, “it would have been obvious under KSR
 to combine the cited teachings of Maes and Ransom be-
 cause Ransom’s REST API is a common web service model
 that provides similar functionality and has several design
 advantages over Maes’ SOAP API, such as increased inter-
 face flexibility and lower bandwidth requirements.”
 J.A. 68. Documentary evidence and the declaration of Dr.
 Nielson, Telesign’s expert, supported the Board’s finding.
 See J.A. 5493–95, 5499–5500. Dr. Nielson explained that
 “[a] skilled artisan with a preference for REST would un-
 derstand that using REST conventions instead of SOAP to


     4   Indeed, Twilio points to the same language in claim
 1 that the Board held would be deemed redundant to sup-
 port its position that an API must be identifiable by its
 URI. Appellant’s Opening Br. at 38.
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 8                       TWILIO INC.   v. TELESIGN CORPORATION



 implement a web service API would be straight forward
 and with an almost certain chance of success.” J.A. 5493.
 He then explained that a person of skill in the art would be
 motivated to make such a modification because “REST has
 a flexible interface and requests and responses can be
 short, resulting in lower bandwidth consumption,” and
 “that it is lightweight, has human readable results, and is
 easy to build with no toolkits required.” J.A. 5494. Sub-
 stantial evidence supports the Board’s motivation-to-com-
 bine finding.
                       2. The ’465 Patent
     Like the ’376 patent, the ’465 patent generally relates
 to a method and system that allow development of teleph-
 ony applications using existing web development tools and
 resources. ’465 patent at 1:61–2:3. The claims of the ’465
 patent specifically relate to a method of processing a te-
 lephony communication involving mapping of a URI, which
 allows a telephony session to be converted into a format
 that may be handled with standard web servers and appli-
 cations. Claim 1 of the ’465 patent is illustrative: 5
     1. A method for processing a telephony communi-
     cation comprising:
     associating an initial URI with a telephony end-
     point;
     initiating a telephony voice session for a telephony
     communication to the telephony endpoint;
     mapping the initial URI to the telephony session;
     sending an application layer protocol request to an
     application resource specified by the URI and




     5   Twilio’s challenges on appeal are limited to the lim-
 itations of claim 1 of the ’465 patent.
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 TWILIO INC.   v. TELESIGN CORPORATION                       9



     embedding state information of the telephony voice
     session in the request;
     receiving a response to the application layer proto-
     col request sent to the application resource,
     wherein the response includes a document of te-
     lephony instructions; and
     executing telephony actions during the telephony
     voice session according to a sequential processing
     of at least a subset of the telephony instructions of
     the response.
 (emphasis added). The Board held claims 1–6, 9, and 13 of
 the ’465 patent obvious in view of the combination of Maes
 and Ransom. Twilio argues that substantial evidence does
 not support the Board’s findings that the mapping and
 sending limitations were taught by the combination of
 Maes and Ransom, or that a person of ordinary skill in the
 art would have been motivated to combine the references.
 Substantial evidence supports the Board’s findings.
                    A. The Mapping Limitation
     The Board found that “the combination of Maes and
 Ransom teaches sending a message that includes both the
 URI specifying the assigned application and information
 about the telephony session, thereby mapping the URI to
 the telephony session.” J.A. 13. Twilio argues that the
 Board did not address how Maes’ message to an application
 maps the initial URI to the telephony session. We do not
 agree. Maes teaches assigning an application to take a call,
 and when the application is assigned, the TEL address is
 passed to the application for the duration of the call.
 J.A. 5218 at 15:58–62. Ransom teaches that the URI “de-
 fines the resource that is being accessed,” and that it was
 well known to send information over the Internet to an ap-
 plication using a URI. J.A. 5282 at [0162]–[0163]. The ap-
 plication, which may be defined by a URI, is mapped to the
 telephony session when it is assigned to take the call and
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 10                      TWILIO INC.   v. TELESIGN CORPORATION



 when the TEL address (the telephony gateway address con-
 taining information about the telephony session) is passed
 to the same application for the call’s duration. In other
 words, the combination of Maes and Ransom teach “assign-
 ing an application specified by a URI to incoming call in-
 formation (i.e., a telephony endpoint), thereby associating
 a URI with a telephony endpoint,” which meets the map-
 ping limitation. J.A. 17. Accordingly, we conclude that
 substantial evidence supports the Board’s finding.
                   B. The Sending Limitation
      The Board found that Maes teaches “sending an appli-
 cation layer protocol request to an application resource
 specified by the URI and embedding state information of
 the telephony voice session in the request” as required by
 claim 1. J.A. 15. Twilio argues that substantial evidence
 does not support the Board’s finding because Maes does not
 teach or suggest that the duration of the call is “embedd[ed]
 state information” as claimed. 6 Contrary to Twilio’s posi-
 tion, Maes teaches passing the TEL address to the applica-
 tion for the duration of the call. J.A. 5218 at 15:58–62. The
 Board found that the TEL address, which is the telephony
 gateway address, is state information akin to the examples
 of state information referenced in the ’465 patent—“[s]tate
 information included with each request may include a
 unique call identifier, call status data such as whether the
 call is in-progress or completed, the caller ID of the caller,
 the phone number called, geographic data about the call-
 ers, and/or any suitable data.” J.A. 18; ’465 patent at 5:33–


      6   Twilio separately argues that even if the TEL ad-
 dress is state information, it was not “embedded” within
 the request. We hold that Twilio waived this argument by
 failing to raise it before the Board, and we will not consider
 it for the first time on appeal. See HTC Corp. v. Cellular
 Commc’ns Equip., LLC, 877 F.3d 1361, 1368 n.3 (Fed. Cir.
 2017).
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 TWILIO INC.   v. TELESIGN CORPORATION                     11



 37. Because Maes teaches passing the TEL address to the
 application for the duration of the call, we conclude that
 substantial evidence supports the Board’s finding that
 Maes teaches the sending limitation.
                     C. Motivation to Combine
     The Board found that a person of ordinary skill in the
 art would be motivated to combine Maes and Ransom to
 achieve the invention claimed in the ’495 patent. J.A. 24–
 26. Twilio argues that the Board failed to sufficiently ar-
 ticulate a motivation to combine Maes with Ransom to
 achieve the associating and mapping limitations in claim
 1. We conclude that substantial evidence supports the
 Board’s motivation-to-combine finding. The Board found
 that a person of ordinary skill in the art would understand
 Ransom as explicit support of the understanding that it
 was well known to use a URI to send a message to an ap-
 plication over the Internet, as disclosed in Maes. J.A. 26.
 The Board was not relying on Ransom to modify the archi-
 tecture disclosed in Maes, but instead to show that the com-
 bination expressly teaches using a URI to achieve the
 embodiment claimed in the ’465 patent. As Dr. Nielson ex-
 plained, a person of ordinary skill in the art would consider
 Ransom’s express disclosure of use of URIs to better
 achieve Maes’ goals of using Web APIs and Internet-based
 technologies. See J.A. 5417. Accordingly, substantial evi-
 dence supports the Board’s finding that a person of ordi-
 nary skill in the art would be motivated to consider Maes
 and Ransom as a combination that expressly discloses the
 limitations of claim 1 of the ’465 patent.
                          CONCLUSION
     We have considered the parties’ remaining arguments
 and find them unpersuasive. Because the Board did not
 err in its analyses and substantial evidence supports the
 Board’s findings, we affirm.
                          AFFIRMED
