Navigating Claim Construction and Broadening Amendments: Lessons from Sisvel v. Sierra Wireless

by Dennis Crouch

In 2019, Sisvel began asserting its U.S. Patent Nos. 7,433,698 and 8,364,196 against cell phone makers, wireless chip suppliers, and cellular network operators. These patents claim methods and systems for exchanging frequency information between a mobile station and a mobile switching center to facilitate switching a mobile device’s connection point within a cellular network. Several defendants petitioned the Patent Trial and Appeal Board (PTAB) for inter partes review (IPR), arguing that the challenged claims were invalid as anticipated and/or obvious based on prior art references. The PTAB instituted IPR and ultimately issued final written decisions concluding that the claims were unpatentable. See IPR2020-01070, Paper No. 31 (PTAB Nov. 8, 2021); IPR2020-01071, Paper No. 30 (PTAB Nov. 8, 2021).

On appeal to the Federal Circuit, Sisvel challenged the PTAB’s claim construction of the term “connection rejection message” and its denial of Sisvel’s revised motion to amend the ‘698 patent claims. The Federal Circuit, in an opinion authored by Judge Stark and joined by Judges Prost and Reyna, affirmed on both issues. Sisvel International S.A. v. Sierra Wireless, Inc., No. 22-1387 (Fed. Cir. September 1, 2023).

Claim Construction

The claims at issue particularly focus on the use of a “connection rejection message” to confer certain information to a mobile device.  The term is used throughout both the patent specification and the claims.  However, it is not expressly defined. The key dispute was it should be construed broadly to mean simply “a message that rejects a connection” or narrowly limited to “a message from a GSM or UMTS telecommunications network rejecting a connection request from a mobile station.”  As is usual for IPR proceedings, the patentee was asking for the narrow construction in order to avoid the prior art.

The Board and the Federal Circuit both applied the Phillips standard. Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc)  Under Phillips, claims are construed according to their plain and ordinary meaning as understood by a person of ordinary skill in the art, looking at the intrinsic evidence including the claims, specification, and prosecution history. Although the specification provides guidance, limitations found within described embodiments should not be imported into the claims absent a clear intent by the patentee to limit claim scope.  Extrinsic evidence, such as dictionary definitions are less important.

On appeal, the Federal Circuit agreed with the PTAB that the plain and ordinary meaning of “connection rejection message” is “a message that rejects a connection.” It found no persuasive basis in the intrinsic evidence to restrict the term only to GSM or UMTS networks. The patentee’s argument here was that the embodiments found in the specification were all directed to UMTS or GSM networks.  But, the problem is that the specification also states that the invention is could work “in many different cellular telecommunications systems” of which UMTS and GMS are two examples. The specification goes on to state that the system work work in any system that involves sending a rejection message in the manner outlined.  Thus, although the specification only the two networks, the court found that the claims and specification were drafted broadly and did not limit the invention only to GSM/UMTS. The court  ultimately declined to confine the claims only to the disclosed embodiments and instead affirmed the broad construction.

Result — invalidity affirmed.

Motion to Amend

Sisvel also challenged the PTAB’s denial of its revised contingent motion to amend claims of the ‘698 patent. The PTAB found the proposed substitute claims impermissibly broadened the scope of the original claims, specifically by changing “based at least in part on” to merely “using” when referring to information from the connection rejection message.  The AIA explicitly prohibits broadening amendments in IPR proceedings. 35 U.S.C. § 316(d)(3) states that amended claims “may not enlarge the scope of the claims of the patent.” Similarly, 37 C.F.R. § 42.121(a)(2)(ii) provides that a motion to amend may be denied if it seeks to enlarge the scope of the claims.

Sisvel contended that when all limitations were considered together, the substitute claims were narrower overall. On appeal, the Federal Circuit explained that a claim is broadened if it is broader in any respect–even if narrowed in some other respects, if it is broadened in any respect. Here, the change from “based on” to “using” broadened the claims by removing the requirement that the frequency parameter impact the value.

Key Takeaways

In hindsight, this is a situation where the patentee could have drafted the claims in these patents in a way that would have at least avoided the arguments raised here.  Of particular note, it often makes sense to include a dependent claims that narrow aspects of the claim to the same level provided by the embodiments. Here, the court also latched-onto throwaway language in the specification stating that the system could work on any network even though the rest of the specification focused on GSM and UMTS networks.  Still, at the time the statement likely made sense as an attempt to explain why it was proper to allow claim scope that is not limited to those networks.

51 thoughts on “Navigating Claim Construction and Broadening Amendments: Lessons from Sisvel v. Sierra Wireless

  1. 6

    The silly part about this is even if the patentee won the claim construction and limited the claims to a message received from a specific type of network, that would still be obvious absent some extraordinary showing.

    “Our claims do this thing the prior art described but on a GMT or UMTS network and not a CDPE network!!!” is not a workable strategy.

    1. 6.2

      “ “Our claims do this thing the prior art described but on a GMT or UMTS network and not a CDPE network!!!” is not a workable strategy.”

      Oh, really? I have some sad news for you: this is the ONLY strategy employed by 99% of the algae eaters who draft and prosecute computer logic claims. The strategy of the remaining 1% is to simply toss in whatever super trendy buzzword the PTO is enamored with at the moment.

      1. 6.2.1

        Brush away the mindless invective and you are left with….

        Well, nothing.

        As usual from Malcolm (but believe him folks, he’s not anti-patent )

  2. 5

    “Patent Quality ” can mean lots of things, but the fundamental thing is simply surviving legal challenge. Quality patents aren’t easily killed.

    Consistency and reliability in legal outcomes is beyond the control of the office, which makes no law and sets no policy.

    Administrative Quality is a whole other measurement.

    Innovation Quality is yet another entirely different domain. Do better inventions make better patents?

    Of course they do, but low-quality patents can still reflect high quality inventions.

    The quality of patents is inescapably tied to the quality of the law and policy acting on them.

    1. 5.1

      The ‘appropriate’ clarification (of course) is that when the term “patent quality” is used, most often people really mean “patent examination quality.”

    2. 5.2

      “Patent Quality ” can mean lots of things, but the fundamental thing is simply surviving legal challenge.

      Exactly. This is really the measure by which all other aspects of the patent process (search, examination, re-exam, etc) are rightly evaluated. A “quality” patent is (at a minimum) one that can survive a validity challenge. Perhaps an even more precise definition would take into account the ability of the patent to block effective competition in the market (a patent that survives validity challenge but loses on infringement is—in some sense—of “lower” quality than one that also wins on infringement).

      The examination process, however, cannot really evaluate the market value of a set of claims. The most that the examination process can assess is validity. Therefore, a “quality” search and a “quality” examination are the sort that result in a patent that will survive validity challenges post-grant.

      It is important to be clear about the meanings of these terms, because it is impossible to assess whether the PTO is doing a “quality” just unless on first knows that “quality” means. All varieties of “quality” in the patent world derive ultimately from a standard of “quality” that relates to the ability to survive a validity challenge.



          Asked by Drum, and intimated by Ygliases, the better “why” is why does Greg continue his Kool-Aid binge with such Sprint-Left propaganda (and how deep has he dived into that Kool-Aid)

      1. 5.2.2

        “ it is impossible to assess whether the PTO is doing a “quality” job unless one first knows what “quality” means”

        Totally unlike terms such as “better” or “highly creative” which are tossed about glibly to differentiate the super amazing abilities of a human using “generative AI” compared to a human “using a computer.”

        How are these awesomely “intelligent” spell checkers working for everybody, by the way?

        LOL. Just kidding. I’m sure it will all be near perfect in, oh, six months or so.


          You still haven’t bothered understanding the tech that you want to diss, have you Malcolm?

          That’s just not a very intelligent thing to do. Even for you.

    1. 4.1

      Dear anon, thanks for the Link. Of course I knew about the debate about quality at the EPO but had not seen this article on it. Looks at first glance like a very fair description of the terms of debate. I would encourage everybody with an interest in patents in Europe to read it too.

      I am told by a colleague whose main case load is filing oppositions at the EPO that the “quality” of patentability searching at the EPO is not what it used to be. That’s OK with him though: it simplifies his task of delivering to his corporate client (in the USA) one patent revocation after another, based on art the EPO could have found and, in his opinion, should have found.

      My practice is on the other side of the fence, arguing cases through to issue by the EPO. I have not seen any diminution of “quality”. To the contrary. I would say that these days I am more likely to get to issue a claim of a scope commensurate with the client’s contribution to the art, and no more than that.

      But hey, what does that anecdotal evidence tell us about the wisdom (or otherwise) of EPO management’s efforts to balance fee levels with quality of work product?

      1. 4.1.1

        Max, does the EPO still farm out some of its prior art searches to national patent offices [with varying search quality]?


          Sorry, Paul, but I have no idea. For quite some years now, I don’t recall anybody mentioning that. I would be somewhat surprised if it’s still going on.

          In house, EPO Examiners are under such time pressure that they can’t spend as much time searching as they would like. I presume that doing their own searches is faster than farming it out to an outside searcher.

          But hey, what would you do, as EPO management, to deliver maximum shareholder value?


            I suppose it may depend on how you define “shareholder” and then take that definition and contrast it with the (proper) legal mission.


              The shareholders of the EPO are the Member States of the EPC, who sit on the Administrative Council and await dividends paid out to them by the EPO President, who just happens to be a past master at persuading the smaller Member States to vote through whatever “reforms” his business advisers come up with.

              Of course, those Member States also have their own national Patent Offices. Isn’t it curious, that the EPO is owned by its business competitors?


                I was thinking along the lines of “stakeholder” being swept into the ‘modern’ definition of “shareholder.”

                But I would suggest that ALL patent law is — and ever has been — Sovereign-centric.

                I will grant that Europe may have a slightly different wrinkle, given that there had been a sense of evolution of European sovereignty these past fifty years, akin to a United States of Europe.

                In that sense, “business competitors” as you use the term, is a bit cloudy.

    1. 3.1

      Thank you – in a nutshell, Judge Newman has passed with flying colors a second independent cognitive evaluation in an apparent rebuttal to the July 31 (self-serving) panel denigration of her first successful evaluation.

      1. 3.1.1

        “passed with flying colors a second independent cognitive evaluation”

        One wonders: Did she mention her obvious disordering of her lived life experience and that of those around her? Or did she leave that part out?


          You keep on wanting to play ‘armchair’ doctor while continuing to want to 1gn0re what real doctors have provided.

          That’s just not a good look for you there, 6.


            I have to give them credit, it does mention in the article that supposedly the doctors did consider the circumstances, or some such word, surrounding her having to come visit. But one wonders how in depth they went in discussing those circumstances.


              In depth enough for the explicit purposes of the event — and directly on point to refute the attempted illicit purge of a Federal Judge.


                “In depth enough for the explicit purposes of the event ”

                Which event?

                In either event, it doesn’t seem like they looked very hard into whether she is straight delusional regarding her staffer being a traitor/not trustworthy and how much disorder that caused.

      2. 3.1.2

        “and unusually cognitively intact 96-year-old woman…”

        Spoiler that means she’s good at masking. Derpa. Why p-sychologists never seem to recognize this in the wild is beyond me.

      3. 3.1.3

        “Dr. Carney opined that “Judge Newman demonstrated no substantial emotional, medical, or psychiatric disability that would interfere with continuation of her longstanding duties as a Judge in the U.S. Court of Appeals.””

        Probably true, but somewhat irrelevant to what is happening, the disordering of the lived life experiences of the people involved.


          Your opinion is both off AND not at point.

          I do wonder why you have become so convinced in your own waywardness.


            “Your opinion is both off AND not at point.”

            I’m pretty sure that nobody gives two fcks about the “state of newman’s mind”, they care about the disordering to their lives and the functioning of the court (inclusive of production of opinions but that’s probably but a mere half concern tbh). This is true of almost all disorders btw.


              Your views on the Judge Newman matter remind me of this:

              link to

              You seem to think that just because you say “this is the issue.” That what you say IS the issue.

              It is not.

              The heart of the issue is the very thing that you just denied.

              (two minutes after this post of yours – above – you seem to backtrack a little)


                “You seem to think that just because you say “this is the issue.” That what you say IS the issue.”

                Uh yeah, that’s the issue that I’m raising, and it’s the issue that the court is raising as well, though they didn’t make themselves explicit just yet. People can actually raise issues of their own anon. It’s allowed.

                1. The issue that YOU are raising is off-point to the actual issue on the table with the CAFC’s attempt to oust a Federal Judge they happen to not like because she does not hew to The Narrative.

                  I never said that you could not raise issues. I continue to point out that your choice is just not material to the point at hand.

                  This has been crystal clear.

    2. 3.2

      LOL – studies commissioned by a Koch-funded group of anti-government a h 0 l e s headed by a (surprise!) university of Chicago ignoramus t u r d.

      Sure, why not.

      1. 3.2.1

        … is that anything like the anti-US Soros funded “a h 0 l e s“…?

        Or is that merely more of your gaslighting “but I am not anti-patent” feelings shining through?

      2. 3.2.2

        … please provide your basis of “Koch funded,” or is any view of being against an inordinate Administrative State enough for you and your one-bucket tendencies?

      3. 3.2.3

        This guy?

        “Philip Hamburger, Chief Executive Officer
        Maurice & Hilda Friedman Professor Of Law, Columbia Law School
        Philip Hamburger is a scholar of constitutional law and its history at Columbia Law School. He received his bachelor’s degree from Princeton University and his J.D. from Yale Law School. Before coming to Columbia, he was the John P. Wilson Professor at the University of Chicago Law School. He also taught at George Washington University Law School, Northwestern Law School, University of Virginia Law School, and the University of Connecticut Law School. Professor Hamburger’s contributions are unrivaled by any U.S. legal scholar in driving the national conversations on the First Amendment and the separation of church and state and on administrative power. His work on administrative power has been celebrated by organizations like the Manhattan Institute and the Bradley Foundation, among others.”

        Out of all those schools listed, you pick University of Chicago to judge him? Do you really practice patent law somewhere, because that selective focus is frightening.


          “ Out of all those schools listed, you pick University of Chicago to judge him? ”

          I “judge” him because he’s an insufferable h-roid who needs to be tarred and feathered and lit on fire. The fact that he was involved with a law school notorious for churning out rightwing dirtbags was merely worth noting for its predictability.


              Wow, I really hope you do not practice law.

              Broadly speaking, all participants on this board can be sorted into two categories: (1) those who post under their own names; and (2) those who do not.

              The people in the first category can be easily verified in an objective and reliable manner as lawyers or non-lawyers. For example, Paul F. Morgan verifiably is a (retired) lawyer, while Martin Snyder is verifiably not.

              Those in the second category are a little bit harder to know. There are, of course, pseudonymous posters like “Ben” who purport not to be lawyers, so there is no reason why anyone should spend time wondering whether they are lawyers.

              Then there are posters (e.g., Atari Man or your own self), who do purport to be lawyers, and whose conversation and content bespeaks a legal education and a daily involvement with the legal profession. The rest of us cannot know that such people are lawyers, but that conclusion seems more likely than not.

              Finally, there are posters who purport to be lawyers, but whose conversation and content give no evidence of legal education or actual familiarity with law that goes beyond what can be gleaned from watching Schoolhouse Rocks videos. Once again, one cannot know whether such posters are lawyers, but that conclusion seems unlikely.

              Each of us must decide for himself or herself how to class participants such as anon or The Prophet. I know how I class each of them, but my own opinions on those points count for no more than anyone else’s.


                Hitting the George Carlin filter…

                In pieces then.

                I still find it hilarious how myopic Greg is.

                I bet that he was one of those that cheered when Hilary sh0ved her foot in her mouth and used the term “depl 0 rables” Which – more than a bit ironically – was part of the reason Trump won. Let me reiterate that I have never voted for Trump.

                Greg is one of those who thinks WAY too highly of himself, as he has spewed Latin, and drinks deeply of the propaganda of the Sprint Left crowd, while 1gn0ring the fact that THIS forum, while certainly dealing with legal matters, is NOT a formal court or executive branch administrative agency forum.

                1. He unwittingly reacts emotionally, instead of engaging me on the substantive points because I have routinely shown his shortcomings. Perhaps he feels it somehow ‘unfair’ that I can employ both facts and derision, while he attempts to ‘play polite’ with his decorum. Certainly, he is not always off-point, and I will give him credit where credit is due. But he is absolutely unable to reciprocate, and this is (sadly, often) tied to his non-patent law Kool-aid drunkenness and even his ‘Big Pharma’ patent law elitism.

                  In short, Greg can bite me for his p00r choices on this forum, and can continue to pretend to not see my posts as they EVER continue to obtain the higher ground that he deigns himself to hold.

                2. Seriously..?

                  Your comment is awaiting moderation.

                  September 9, 2023 at 8:06 am

                  Wow — after numerous tries, it have to p u n t on a middle paragraph. All seemingly possible offending words to the George Carlin filter were screened out and still cannot get past the filter.


            Your feelings are noted Malcolm – more of the same emotive “one-bucketing while not caring about the actual positions or even context.”

            But tell everyone again how you are not anti-patent.


            “I “judge” him because he’s an insufferable h-roid who needs to be tarred and feathered and lit on fire.

            Wait are we talking about Bernie Sanders?

            “The fact that he was involved with a law school notorious for churning out rightwing dirtbags was merely worth noting for its predictability.”

            Let me take a wild guess, there’s a huge amount of muggings around that university campus isn’t there?


              Careful 6 – you are f1r1ng on Malcolm’s narrative and you will likely end up in the same ‘one bucket’ as all the deplorables (including Judge Newman).

  3. 2

    The DoC OIG has released it’s report on the PTO’s classification and routing efforts.

    Key findings:

    I.USPTO did not ensure effective contract oversight for classification services.
    II. USPTO lacked adequate controls to ensure that classification challenges were efficiently and effectively submitted and adjudicated.
    III. USPTO did not effectively design and implement Cooperative Patent Classification system-based routing.

    link to

  4. 1

    “ Sisvel contended that when all limitations were considered together, the substitute claims were narrower overall.”

    In other words, they flat out l i e d about the controlling law, which can be looked up in five seconds. Sanctions?

    1. 1.1

      “Claim broadening” has been so thoroughly defined in reissue, reexamination and IPR judicial decisions as broadening in any respect [even if other parts of the same claim are narrowed] that an attorney making an argument to the contrary here is incomprehensible.
      As for claim scope interpretation, this is another case of an attempted “nose of wax” claim interpretation [bent one way for validity and the other way for infringement] getting straightened in an IPR wringer.

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