The CAFC Finds the Board’s Claim Construction to Be Unreasonably Broad
| April 13, 2018
In re Power Integrations, Inc.
March 19, 2018
Before Moore, Mayer, and Stoll. Opinion by Mayer.
Summary
Power Integrations, Inc. (“Power Integrations”) appeals a remand decision of the Patent Trail and Appeal Board (“Board”) rejecting claims 1, 17, 18 and 19 of US Patent No. 6,249,876 (the ‘876 patent) as anticipated under 35 U.S.C. §102(b). On appeal, the CAFC found the board’s claim construction to be unreasonably broad. Because the Board’s anticipation rejection was based on an unreasonably broad claim construction, the CAFC reversed.
要旨:
連邦巡回控訴裁判所(CAFC)の判決である。先に米国特許庁審判部へ差し戻され、米国特許庁審判部が再度判断を下したその判断の適否が争われた。米国特許庁審判部が広いクレーム解釈に基づいて「新規性なし」と判断した審決をCAFCは覆した。CAFCは、米国特許庁審判部のクレーム解釈はいわゆるBRI(Broadest Reasonable Interpretation)ではなく、Unreasonably(不当)に広いと判断した。そのような不当に広いクレーム解釈に基づいて引例の開示が当てはめられた新規性の判断が覆された。
Details
The ‘876 patent is directed to a technique for reducing electromagnetic interference by jittering the switching frequency of a switched mode power supply. Representative claim 1 is reproduced below. Fig. 1 from the ‘876 patent is also set forth below.
- 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.
FIG. 1 of the ‘876 patent
Procedural Background
In 2004, Power Integrations sued Fairchild Semiconductor International, Inc. (“Fairchild”) in the United States District Court for the District of Delaware, alleging Fairchild had willfully infringed the ’876 patent. Fairchild raised an invalidity defense asserting that the ‘876 patent was obvious in view of U.S. Patent 4,638,417 to Martin. A jury rejected Fairchild’s invalidity defense and found that Fairchild willfully infringed claim 1 of the ‘876 patent.
In the district court, Fairchild’s invalidity defense turned on the meaning of the term “coupled” in the context of the language “the digital to analog converter coupled to the counter” in claim 1. The district court adopted Power Integration’s construction of the term “coupled” as requiring that two circuits be connected in a manner “such that voltage, current, or control signals pass from one to another” with “the recited coupling…present for purposes of control.” The district court emphasized that its construction did not require a direct connection or preclude the use of intermediate circuit elements. The Martin patent included an erasable programmable read only memory (EPROM) between the counter and the digital to analog converter, and, in Martin, the digital to analog converter was not considered “coupled” to the counter in a manner such that voltage, current, or control signals pass from one to another.
On appeal to the Federal Circuit, the CAFC affirmed the jury’s finding that the ‘876 patent was not invalid for obviousness. The Federal Circuit noted that the “salient difference” between the ’876 patent and Martin is Martin’s inclusion of an erasable programmable read only memory (“EPROM”) between the counter and the digital to analog converter and “does not teach removing the EPROM . . . as in the ’876 Patent.”
In December of 2006, while district court proceedings were pending, Fairchild instituted an ex parte reexamination proceeding against claims 1, 17, 18 and 19 of the ‘876 patent. During ex parte reexamination the board affirmed the examiner’s rejection of claims 1, 17, 18 and 19 as anticipated by U.S. Patent No. 4,638,417 to Martin, as well as two other references (Habetler and Wang).
Each of the Martin, Wang and Habetler references included a ROM separating a counter from a digital to analog converter. Power Integration, adopting the district court’s claim construction, argued that, “the respective counters in Martin, Wang and Habetler are not coupled to the respective digital to analog converters because they disclose a ROM separating a counter from a digital to analog converter.” However, the board rejected Power Integration’s argument and relied on one of a number of definitions of “couple” from a generalist dictionary to determine that the term “couple” means, “to join (electric circuits or devices) into a single …circuit.” Applying this construction, the Board held that Martin, Wang and Habetler each disclosed a counter “coupled” to a digital to analog converter because the two components were joined in one circuit.
The Board denied Power Integration’s petition for rehearing. Power Integration then appealed to the CAFC. The CAFC vacated the Board’s decision, explaining that the board had failed to thoroughly and fully assess Power Integration’s claim construction position, which was expressly tied to the district court’s claim construction.
The CAFC acknowledged that the board is generally not bound by a prior judicial construction and that in reexamination the board applies a different claim construction standard than the district court. However, the CAFC concluded that because Power Integration’s principal claim construction argument was expressly tied to the district court’s claim construction, the board had an obligation to evaluate that construction and determine whether it was consistent with the broadest reasonable construction of the term.
On remand, the board concluded that a comparison of its construction with that of the district court was unwarranted. In the board’s view, a district court’s claim construction is typically narrower than the broadest reasonable construction of a term. The board once again affirmed the examiner’s rejection of claims 1, 17, 18 and 19 as anticipated, and continued to adhere to the generalist dictionary definition of the term coupled.
Before the CAFC
In reviewing the board’s remand decision, the CAFC acknowledged that while the broadest reasonable interpretation standard applied by the board during reexamination is broad, it does not give the board unfettered license to interpret the words in a claim without regard to the full claim language and the written description. The court emphasized that even under the broadest reasonable construction rubric, the board must always “consider the claims in light of the specification and teachings in the underlying patent.”
The CAFC concluded that the board’s claim construction was unreasonably broad and improperly omitted any consideration of the disclosure in the specification. The CAFC pointed out that the board’s construction relied exclusively on a definition from Webster’s Dictionary to determine that the “coupled” limitation requires only that two components be “join[ed] . . . into a single . . . circuit.” The CAFC criticized that 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.
Not only did the board’s claim construction omit any consideration of the disclosure in the specification, the CAFC explained that the board’s unduly broad reading of the claim language was unsupported by the specification. The court pointed out that the ‘876 patent describes that it strives to eliminate unnecessary components and create a more compact circuit. However, the 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.
Furthermore, the court noted that every embodiment disclosed in the ‘876 patent shows a counter that passes voltage, current or control signals to the digital to analog converter.
Moreover, the court looked at the plain language of the claim itself, and emphasized that by its plain terms, claim 1 requires the counter to “caus[e] the converter to adjust the control input and to vary the switching frequency”.
Because the board’s decision affirming the examiner’s rejection of claims 1, 17, 18 and 19 was based on an erroneous claim construction and the rejection is not supported under the proper construction, the CAFC reversed the board’s rejection of claims 1, 17, 18 and 19 under §102.
Comments
The district court and the board used different claim construction standards (ordinary and customary meaning (Phillips standard) vs. broadest reasonable interpretation (BRI)) and obviously came to different conclusions. The CAFC found that under a properly applied BRI standard, the board’s resulting claim construction should be the same as the district court’s construction.
Tags: 35 U.S.C. §102 > anticipation > broadest reasonable interpretation > claim construction
