By Mark Engstrom, J.D.
Two patents on a system for handling Internet requests for webpages containing dynamic content were not anticipated by a prior-art method of "URL redirection," the U.S. Court of Appeals for the Federal Circuit has ruled, affirming a finding by the Patent Trial and Appeal Board. Nevertheless, the Board failed to address an alternative argument by appellants Microsoft and International Business Machines (collectively, "Microsoft"), which claimed that both of the patents—owned by appellee Parallel Networks—were anticipated by a prior-art method that involved "request forwarding" and the modification of UNIX socket packages. In addition, the Board failed to provide adequate support for a "decisive" component of its obviousness analysis. The Federal Circuit thus affirmed the Board’s rejection of Microsoft’s anticipation challenge based on the prior-art method of URL redirection, vacated the Board’s rejection of Microsoft’s anticipation challenge based on the prior-art method of modifying UNIX sockets, and vacated the Board’s rejection of Microsoft’s obviousness challenge. The vacated issues were remanded to the Board for further consideration (Microsoft Corp. v. Parallel Networks Licensing, LLC, December 1, 2017, Taranto, R.).
Patent. Parallel Networks Licensing owns U.S. Patent Nos. 5,894,554 and 6,415,335 (hereinafter, the "Parallel Patents"), which address the problem of processing a large number of requests for dynamic webpages. The patented solution uses a partitioned architecture that comprises a web server, an interceptor, a dispatcher, and multiple page servers, and the basic method of the challenged claims involves four steps: (1) a webpage request is sent to a web server; (2) the request is intercepted; (3) an appropriate page server is identified for the processing of the request; and (4) the request is routed to the identified page server.
Procedural Posture. Parallel sued Microsoft and IBM for the infringement of the Parallel Patents, and the defendants sought inter partes reviews (IPRs) of both patents. The Patent Trial and Appeal Board instituted IPRs for all of the challenged claims—on the asserted grounds of anticipation and obviousness—and consolidated the claims into two proceedings, one for each of the Parallel Patents (with Microsoft and IBM as petitioners). After conducting the IPRs, the Board found that the petitioners failed to prove anticipation or obviousness. On appeal, the appellants argued that the Board had erred by: (1) changing the "agreed-to simple construction" of the claim term "request" and (2) rejecting their arguments for unpatentability.
Prior art. The prior art at issue—a 1995 publication by Daniel Andreson and others (SWEB: Towards a Scalable World Wide Web Server on Multicomputers, Dept. of Computer Sci. Tech. Report TRCS95-17, U.C. Santa Barbara (Sept. 1995), hereinafter "SWEB")—disclosed a "scalable Web server" that efficiently processed a large number of simultaneous requests using a cluster of workstations and parallel machines.
The prior-art system comprised multiple webservers that either: (1) acted as a page server, when appropriate, or (2) identified another server—based on dynamic system load information—that could get the desired information to the client computer more efficiently. SWEB stated that its preferred process for the second method was "URL redirection." The primary advantages of URL redirection were simplicity and universal compatibility, according to SWEB. Nevertheless, SWEB also identified other server-changing processes that would supply the desired information to the client computer.
For example, SWEB stated that a server other than the initially contacted server might better serve the client computer. If that was the case, the "best" solution would be to "modify the UNIX sockets package" so the initially contacted server would send the request directly to the desired web server. SWEB noted, however, that the modification required a "substantial modification of the UNIX operating system kernel," which would be "difficult."
Claim construction. The only term that Microsoft challenged on appeal was the claim term "request" in the phrase "dynamic Web page generation request." The Board construed that term as "a message that asks for a Web page"—a construction that the parties had agreed to during the pending district court litigation. The Board concluded that, under that construction, each time the client computer sent a message asking for a web page, it made a new request.
Microsoft argued that the Board should have focused on the content that the client computer was requesting, not on the individual acts of asking. As long as the content was the same, the Board should have treated multiple acts of asking as a single "request." The Federal Circuit disagreed.
First, there was "at best" an ambiguity in the term "message," since the term could have referred to "substantive communicative content" or "a discrete act of utterance to convey communicative content." But if an ambiguity was present, it was apparent on the face of the term, and Microsoft had agreed to the term "message" as the defining construction in the district court, leaving it for the fact finder to apply. And in the present proceedings, Microsoft did not ask the Board for further claim construction.
Second, the patent involved computers that "sent" communications that other machines had to "process," and both the sending and the processing required an expenditure of "precious time and scarce resources." In that context, the "more natural" understanding of the terms "request" and "message" was one that was limited to a discrete act of communicating, not one that "equates discrete utterances" when those utterances convey the same content.
For those reasons, the court rejected Microsoft’s assertion that the Board had committed a claim-construction error.
URL redirection. Substantial evidence supported the Board’s finding that the web client in SWEB’s "URL redirection" disclosure made two separate requests, as that term was used in the Parallel Patents. One request was made when the initial request was sent to the web server that was selected by the DNS server, and another request was made when a request was sent to a second web server that was identified by the scheduler.
Microsoft argued that that the client computer’s "human user" made just one communication in the URL redirection method. That, however, was irrelevant under the Parallel Patents, which referred to a request, a web client request, a web browser request, and URL request "interchangeably." More generally, the patents made it clear that the requesting entity was the user’s computer, not the human user.
Ultimately, the court found no error in the Board’s finding that SWEB’s "URL redirection" method did not anticipate the challenged claims of the Parallel Patents.
Modification of UNIX sockets. According to the court, the Board failed to address Microsoft’s alternative argument for anticipation, based on SWEB’s disclosure of a method involving "request forwarding" and the modification of a recipient server’s UNIX socket packages, where the server forwards a request to a second server without involving the client computer in the initiation of contact with the second server (as in URL redirection). The court agreed that the alternative process was a form of "request forwarding"—a name for what the Parallel Patents required. The court thus agreed with Microsoft that the Board had erred in failing to address the petitioners’ alternative argument.
Obviousness. The Board did not provide a sufficient explanation for its rejection of Microsoft’s obviousness challenge, the court concluded. In Microsoft’s view, the Board failed to give proper effect to the testimony of its expert under the legal standards for obviousness. Referring to that testimony, the Board found that Microsoft had neglected to explain why a person of ordinary skill in the art would have been motivated to modify SWEB’s URL redirection. According to the Board, the stated benefits of request forwarding were already provided by URL redirection.
The Board’s reasoning was inadequate, the court explained, because it failed to address the legal significance of the expert’s "amply supported" statement that request-forwarding was a well-known technique for a request-receiving server to get another server to provide the desired information to the client computer. Significantly, the district court did not address the expert’s statement that an interest in anonymity was a reason for request forwarding, and it did not address SWEB statements suggesting that the "best situation" might be to use a form of request forwarding (by UNIX socket modification) and identifying a "disadvantage" of URL redirection.
Because the Board failed to provide adequate reasoning to support a "decisive" component of its obviousness analysis—and it failed to consider the argument that SWEB taught the method of "UNIX sockets modification"—all of its obviousness rulings were vacated and remanded.
Attorneys: Constantine L. Trela, Jr. (Sidley Austin LLP) for Microsoft Corp. and International Business Machines Corp. Christopher Thor Bovenkamp (McKool Smith, PC) for Parallel Networks Licensing, LLC.
Companies: Microsoft Corp.; International Business Machines Corp.; Parallel Networks Licensing, LLC
MainStory: TopStory Patent FedCirNews
Interested in submitting an article?
Submit your information to us today!Learn More