How Broad is too Broad for the Patent Trial and Appeal Board?

“…glad the CAFC is familiar with patent law concepts and basic logic, because the PTAB seemingly lacks both in its consideration of the present case.”

Ben Brownlow Profile Picture by: Ben Brownlow | March 21, 2018

On March 19, 2018, the United States Court of Appeals for the Federal Circuit (CAFC) issued a precedential opinion[i] concerning a Patent Trial and Appeal Board (PTAB) reexamination proceeding. Circuit Judge Mayer penned the opinion, which reversed a PTAB decision rejecting certain claims of U.S. Patent No. 6,249,876 (‘876 patent) as anticipated by certain references discussed below.[ii] The CAFC’s reversal hinged on the board’s unreasonably broad claim construction upon which it based its anticipation rejections.

In 2004, Power Integrations brought a patent infringement suit against Fairchild Semiconductor (Fairchild) in Delaware federal court.[iii] The district court adopted Power Integrations’ construction of the term “coupled” in claim 1 of the ‘876 patent as requiring two circuits to be connected such that “voltage, current or control signals pass from one to another.

Claim 1 of the ‘876 patent, as amended, recites:

A digital frequency jittering circuit for varying the switching frequency of a power supply, comprising:

an oscillator for generating a signal having a switching frequency, the oscillator having a control input for varying the switching frequency;

a digital to analog converter coupled to the control input for varying the

switching frequency; and

a counter coupled to the output of the oscillator, the digital to analog converter coupled to the counter, the counter causing the digital to analog converted to adjust the control input and to vary the switching frequency of the power supply.

Fairchild argued at trial that U.S. Patent No. 4,638,417 (“Martin”) rendered claim 1 obvious, however the jury returned a verdict of non-obviousness. Fairchild filed a motion for judgment as a matter of law, which the district court denied, and the CAFC affirmed on appeal, explaining that Martin included an erasable programmable read-only memory (EPROM) between the counter and the digital to analog converter and does not teach removal of the EPROM as in the ‘876 patent.

In 2016, the CAFC affirmed a jury determination that claim 1 was not invalid as anticipated by Martin or the Wang reference.[iv] In Power Integrations V, the CAFC concluded that neither reference disclosed claim 1’s “coupled” limitation since both Martin and Wang taught decoupling the counter from the digital to analog converter by using an intermediary EPROM element.

Things were seemingly looking good for Power Integrations. However, even before inter partes review (IPR) was established by the America Invents Act, Fairchild still had another avenue at the patent office through which it could attack the ‘876 patent it was accused of infringing – ex parte reexamination. As illustrated below, even before the IPR process was created, patent owners have been dealing with litigating (and re-litigating) the same issues in different forums with different evidentiary standards and procedures. The net effect of these post grant review proceedings had been an increase in the cost associated with litigating patent cases and less certainty as to whether or not a patent is really worth anything to the patent owner or entity to which it belongs.

In 2006, while district court litigation was still ongoing, the PTO granted Fairchild’s request for ex parte reexamination of the same claims of the ‘876 patent litigated in district court. The PTAB upheld the examiner’s rejection of claim 1 as anticipated by Martin in view of Wang. During a reexamination proceeding, “the PTO must give claims their broadest reasonable construction consistent with the specification.”[v] In its decision, the PTAB rejected Power Integrations’ argument which were found by Article III courts to be a proper legal construction of the term “coupling” in light of the specification and plain reading of the claims. Applying an overly generic construction of “coupling,” the PTAB found that despite the elements not being directly coupled to one another as claimed in the ‘876 patent, the PTAB relied upon one of many generic definitions available for “coupling” in Webster’s Dictionary (1993 ed.), construing the term to mean “to join (electric circuits or devices) into a single . . . circuit.”[vi]

On appeal, the CAFC vacated the PTAB’s decision.[vii] The CAFC acknowledged the board is not bound by prior Article III court claim constructions and the claim construction standard applied in reexamination proceedings differs from that applied in district court. However, the CAFC concluded that the PTAB was obligated to at the very least evaluate whether the claim construction presented by Power Integrations consistent with the district court’s claim construction was consistent with the broadest reasonable construction of the term. On remand, the PTAB employed some interesting and seemingly defiant logic. Although it acknowledged the CAFC’s concern that it did not consider whether the district court’s construction was consistent with the broadest reasonable interpretation of the term, in the same breath it concluded that since the district court’s claim construction tends to be narrower than the broadest reasonable construction of a term, a comparison of its claim construction with that reached by the district court was unnecessary.

In the current appeal of the PTAB’s Remand Decision, the CAFC concluded (again) that the PTAB’s construction of “coupled” was unreasonably broad and failed to provide any consideration of the ‘876 patent disclosure or the claim language itself. In its opinion, the CAFC smacked down the PTAB’s SECOND failed opportunity to resist applying an unreasonably broad interpretation. The CAFC applied some simple logic and established, well-understood precedent regarding claim construction that everyone in the field of patent law should know.

Here are some of the basic concepts presented in the March 19, 2018 CAFC opinion that the PTAB judges may have forgotten (page citations omitted) (emphasis added):

“While the broadest reasonable interpretation standard is broad, it does not give the [b]oard an unfettered license to interpret the words in a claim without regard for the full claim language and the written description.” Trivascular, Inc. v. Samuels, 812 F.3d 1056, 1062 (Fed. Cir. 2016). The board’s claim construction here was unreasonably broad and improperly omitted any consideration of the disclosure in the specification.

Under the board’s overly expansive view of the term “coupled,” every element anywhere in the same circuit is potentially “coupled” to every other element in that circuit, no matter how far apart they are, how many intervening components are between them, or whether they are connected in series or in parallel. See In re Suitco Surface, Inc., 603 F.3d 1255, 1260 (Fed. Cir. 2010) (“The broadest-construction rubric coupled with the term “comprising” does not give the PTO unfettered license to interpret claims to embrace anything remotely related to the claimed invention.”)

Another problem with the board’s claim construction is that it renders claim language meaningless. As discussed above, claim 1 begins by reciting a “circuit” that includes both a counter and a digital to analog converter. The phrase “the digital to analog converter [is] coupled to the counter,” would be superfluous if, as the board said, it means only that the two components are in the same circuit.

Even more fundamentally, the board’s unduly broad reading of the language of claim 1 is unsupported by the specification…[t]he inclusion of a bulky pre-programmed memory between the counter and the digital to analog converter is inconsistent with the ‘876 patent’s focus on minimizing circuit size. See Power Integrations III, 711 F.3d at 1368 (relying on testimony explaining that including a memory between the counter and the converter “adds expense and imposes design constraints” and that because of its components, Martin’s circuit cannot be integrated on a single chip”).

In the board’s view, claim 1 can be expanded to encompass a circuit in which the switching frequency varies based on data from a memory because neither the claim language nor the specification “requir[es] the lack of a memory.” Remand Decision, 2016 Pat. App. LEXIS 11870, at *13. This reasoning is unpersuasive. “The correct inquiry in giving a claim term its broadest reasonable interpretation in light of the specification is not whether the specification proscribes or precludes some broad reading of the claim term adopted by the examiner.” In re Smith Int’l, Inc., 871 F.3d 1375, 1382–83 (Fed. Cir. 2017). Instead, a proper claim construction analysis endeavors to assign a meaning to a disputed claim term “that corresponds with . . . how the inventor describes his invention in the specification.” Id. at 1383. Although the ’876 patent does not expressly exclude a circuit in which a pre-programmed memory is placed between the counter and the digital to analog converter and dictates the converter’s behavior, such an arrangement is inconsistent with both the specification which, as discussed above, emphasizes the need to minimize circuit size and the plain claim language which specifically requires the counter—not some other circuit element—to “caus[e]” the converter to adjust the control input.

The opinion goes on to scold the PTAB for twice failing to conjure any viable interpretation of “coupled” that differs from the construction that already survived in litigation. I’m glad the CAFC is familiar with patent law concepts and basic logic, because the PTAB seemingly lacks both in its consideration of the present case. It’s pretty shocking that the PTAB completely ignored the plain language of the claims read in light of the specification, which, thankfully, the CAFC got right in this instance. Not every patent owner enjoys the financial support needed to ultimately reach the correct legal determination with respect to its intellectual property rights. The PTAB is busier than ever these days, invalidating patents in IPR proceedings left and right in challenges (often brought by third parties compensated by infringing defendants). The net result is an unfair set of rules which unduly punish patent owners while rewarding infringers with yet another avenue to avoid liability for infringing a valid patent.


[ii] See In re Power Integrations, Inc., No. 90/008,326, 2016 Pat. App. LEXIS 11870 (P.T.A.B. Oct. 4, 2016) (“Remand Decision”).

[iii] See Power Integrations, Inc. v. Fairchild Semiconductor Int’l, Inc., 422 F. Supp. 2d 446, 448 (D. Del. 2006) (“Power Integrations I”), aff’d in part, rev’d in part, vacated in part, 711 F.3d 1348 (Fed. Cir. 2013) (“Power Integrations III”)].

[iv] Programmed Pulsewidth Modulated Waveforms for Electromagnetic Interference Mitigation in DC-DC Converters, 8 IEEE Transactions on Power Elecs. 596-605 (1993) (“Wang”).

[v] In re ICON Health & Fitness, Inc., 496 F.3d 1374, 1379 (Fed. Cir. 2007).

[vi] In Re Power Integations, Inc., No. 2010-0011021, 2010 Pat. App. LEXIS 19305, at *7 (P.T.A.B. Dec. 22, 2010) (“Power Integrations II”).

[vii] Power Integrations, Inc., v. Lee, 797 F.3d 1318 (Fed. Cir. 2015) (“Power Integrations IV”).

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