The United States Court of Appeals for the Federal Circuit (“the Federal Circuit”) recently put the United States Patent Trial and Appeal Board (“the Board”) on notice that the broadest reasonable interpretation of claims (“BRI”) is not without limits. U.S. Patent No. 6,249,876 ("the ‘876 patent”), owned by the Power Integrations, Inc. (“Power Integrations”), had its claims 1, 17, 18 and 19 rejected in an ex parte reexamination that was appealed to the Board. The Board, relying on an interpretation allowing additional elements to be disposed between “coupled” elements, supported the examiner’s rejection of the claims as anticipated under pre-AIA 35 U.S.C. §102(b). The Federal Circuit reversed the Board’s decision, labeling the claim construction as “unreasonably broad.” IN RE: POWER INTEGATIONS, INC. (Appellant), 2017-1304 (March 19, 2018).
Claim 1 is set forth below to show its use of “coupled”:
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 converter to adjust the control input and to vary the switching frequency of the power supply.
The Federal Circuit made it clear that it did not agree with the Board’s claim interpretation, citing 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 an unfettered license to interpret claims to embrace anything remotely related to the claimed invention.”
The Federal Circuit provided guidance on the interpretation claim language, and found the Board’s support of its claim construction lacking. The Federal Circuit looked for evidence that the Board:
a. when lacking express definitions, implicit definitions as “. . . may be found in or ascertained by a reading of the patent documents;”
b. evidence of consideration of consistency in specification description, as, for example, between multiple embodiments; and
c. evidence that the board endeavored “to assign a meaning to a disputed claim term that corresponds with . . . how the inventor describes his invention in the specification.”
The Federal Circuit found the Board’s claim interpretation lacking on all of the above. Particularly notable were the Federal Circuit’s observations on:
In light of the deficiencies in the Board’s claim interpretation, the Federal Circuit reversed the rejection of claim 1: “Because the board’s decision affirming the examiner’s rejection of claim 1 was based on an erroneous claim construction and the rejection is not supported under the proper construction, we reverse the rejection of claim 1.” The Federal Circuit extended the reversal to include claims 17, 18 and 19.
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