Patent Owner Warning: Statements/Amendments During Examination Will Be Scrutinized During Litigation

Intellectual Property Law

In Genuine Enabling Technology LLC v. Nintendo Co., Ltd.,1 the Federal Circuit held that statements made during prosecution—to distinguish the prior art on the ground that it taught slow-varying signals whereas the invention utilized audio or higher-frequency signals—only clearly disclaimed claim scope of signals below the audio frequency range. Thus, the resulting disclaimer was commensurate with the specific arguments needed to overcome the prior art rejection.

Genuine Enabling Technology LLC sued Nintendo Co. Ltd. and Nintendo of America, Inc. (collectively Nintendo), accusing five of Nintendo’s products of infringing U.S. Patent No. 6,219,730 (’730 patent).

The ’730 patent discloses technology for joining data streams to save computer resources. The ’730 patent explained that prior art computers accepted user input using a “user input device” (UID), like a mouse or keyboard.2 Computers also had “input/output” (I/O) cards to manage various kinds of signals.3 The ’730 patent described that devices and cards divided computer resources and that their arrangement could be inefficient.4

To avoid these problems, the ’730 patent provided a new type of UID that removed the computer’s sound card so that the UID directly received speech input and transmitted the speech output to the speaker.5 This configuration included the use of a framer that received input from the UID and an external device and that coordinated and combined the data streams.6 Claim 1 recited the following:

1. A user input apparatus operatively coupled to a computer via a communication means additionally receiving at least one input signal, comprising:

user input means for producing a user input stream;

input means for producing the at least one input signal;

converting means for receiving the at least one input signal and producing therefrom an input stream; and

encoding means for synchronizing the user input stream with the input stream and encoding the same into a combined data stream transferable by the communication means.7

During examination, the Patent Office examiner rejected claims 1–27 as obvious, based on U.S. Patent No. 5,990,866 (Yollin). Yollin, titled “Pointing Device with Integrated Physiological Response Detection Facilities,” related to a pointing device with built-in biological response recognition that did not utilize excess I/O ports.8 Yollin also disclosed physiological response sensors that could be used.9 Yollin, though, did not precisely describe the frequencies of the signals produced by the physiological sensors.

In connection with the “input signal” claim language of pending claims 1, 16 and 23, the examiner referred to Yollin’s discussion of “input information received from motion translation unit 102, user selection unit 104 and physiological response sensor(s) 106” in rejecting the claims.10

The inventor, Mr. Nguyen, replied to the office action by differentiating the slow-varying physiological response signals described in Yollin from the claimed signals having audio or higher frequencies used by his own invention to avoid the signal collision problem solved by Mr. Nguyen’s invention:

Yollin’s invention ... utilizes various implementations and configurations for receiving input from motion translation unit 102, user selection unit 104 and physiological response sensor(s) 106, and for processing their information prior to communication to the host system via communication interface 108 and channel 112. These configurations are standard and well-known to the artisan. However, Yollin only uses the configuration to receive the slow varying signal coming from the physiological response sensor(s). Yollin is not motivated and does not anticipate their use for receiving signals containing audio or higher frequencies in place of the physiological response sensor(s). The high frequency input signal, which comes from a source different from those of motion and selection units, will run asynchronously relative to, and collide with, the other signals. Yollin’s invention does not teach or suggest any approach for receiving and recovering that kind of input signal.11

Genuine alleged that five Nintendo products infringed the ’730 patent: (1) the Wii Remote and Wii Remote Plus, (2) the Nunchuk, (3) the Wii U GamePad, (4) the Switch Joy-Con Controller, and (5) the Nintendo Switch Pro Controller.

The parties filed claim interpretations disputing the meaning of the claim term “input signal” in all claims. Genuine asserted the interpretation of “input signal” to be a signal having an audio or higher frequency. Nintendo offered a narrower interpretation:

A signal containing audio or higher frequencies. Mr. Nguyen disclaimed signals that are 500 Hertz (Hz) or less. He also disclaimed signals that are generated from positional change information, user selection information, physiological response information, and other slow-varying information. Alternatively, indefinite.12

Nintendo filed a declaration by Dr. Howard Chizeck to support its proposed claim interpretation, which described the characteristics and function of physiological sensors such as those described by Yollin. Dr. Chizeck was of the view that “the maximum frequency of the signals from physiological sensors described by Yollin is at least 500 Hz.”13 Nintendo contended, citing the Chizeck declaration in support, that a person of ordinary skill would have understood Yollin to disclose physiological sensor signals having maximum frequencies of at least 500 Hz. Therefore, Nintendo argued Mr. Nguyen had disclaimed all signals having maximum frequencies of at least 500 Hz when he distinguished Yollin from the claims during prosecution. Nintendo, therefore, opposed Genuine’s broader proposed interpretation and filed for summary judgment of noninfringement, contending that its accused controllers generated the slow-varying signals that Mr. Nguyen disclaimed, and therefore did not infringe.

The district court granted Nintendo’s motion for summary judgment and interpreted the “input signal” claim language to mean “signals above 500 Hz and excluding signals generated from positional change information, user selection information, physiological response information, and other slow-varying information,”14 as Nintendo asserted. The court held Mr. Nguyen’s characterization of Yollin during prosecution was a disclaimer of slow-varying signals.

The district court rejected Genuine’s assertion that Mr. Nguyen only disclaimed slow-varying signals lower than the audio frequency spectrum. The district court reasoned that while Mr. Nguyen differentiated Yollin because his invention involved audio or higher frequencies, this statement did not erase his additional statements specifically disclaiming as slow-varying the array of frequencies used by Yollin. Based on the disclaimer and resulting interpretation of “input signal,” the district court granted Nintendo summary judgment of no infringement.

Genuine appealed, and the Federal Circuit reversed. The appeals court initially explained that expert testimony, one kind of extrinsic evidence, can be helpful with claim interpretation to, for example, show that a claim term has a specific meaning.15 “However, expert testimony may not be used to diverge significantly from the intrinsic record,” it said.16

Therefore, the intrinsic record “must be considered and where clear must be followed.”17 Thus, the court explained that the use of expert testimony for claim interpretation is allowed when the testimony supports the interpretation based on the intrinsic evidence.18

The court observed that the prosecution disclaimer further prevents the recapture, via claim interpretation, of particular meanings disclaimed during the prosecution/examination process. For a statement/writing to be eligible as a disclaimer of claim scope, it must be “so clear as to show reasonable clarity and deliberateness,” and “so unmistakable as to be unambiguous evidence of disclaimer.”19 The court said, “If the challenged statements are ambiguous or amenable to multiple reasonable interpretations, prosecution disclaimer is not established.”20

On appeal, the parties agreed that Mr. Nguyen disclaimed claim scope during prosecution of the ’730 patent when differentiating his claimed inventions from the Yollin prior art reference. The parties disagreed on whether claim scope of signals that were not below the audio frequency spectrum was disclaimed. Genuine asserted that the prosecution history clearly demonstrated that Mr. Nguyen disclaimed slow-varying signals because Mr. Nguyen created a clear separation between the prior art Yollin’s low-frequency signals and the higher-frequency signals used in his inventions. Genuine also asserted that the district court mistakenly relied on testimony by Nintendo’s expert, Dr. Chizeck, that had no support in the intrinsic record but relied only on extrinsic evidence.

The Federal Circuit agreed with Genuine that there was no disclaimer:

We conclude that the only disavowal of claim scope that is clear and unmistakable in the record before us is Mr. Nguyen’s disavowal of signals below the audio frequency spectrum . . . . Mr. Nguyen repeatedly distinguished his inventions from Yollin on the grounds that Yollin taught “slow-varying signals” whereas his inventions involved “audio or higher frequency” signals . . . . The examiner’s acceptance of that distinction and resulting decision to allow the claims suggest that Mr. Nguyen and the examiner reached an understanding on that point. To the extent Mr. Nguyen’s statements may implicate other claim scope—such as signals of frequency up to 500 Hz—the record does not rise to the level of establishing a “clear and unmistakable” disavowal.21

Therefore, the court determined that the district court incorrectly interpreted “input signal,” and construed it to mean “a signal having an audio or higher frequency.”22 In addition, the Federal Circuit found the district court incorrectly held that Mr. Nguyen disclaimed all signal frequencies other than signals below the audio frequency spectrum and mistakenly relied on the expert testimony of Dr. Chezeck to limit the claim scope to signals above 500 Hz.23 Accordingly, the Federal Circuit reversed the district court’s grant of summary judgment of noninfringement.

Practice Pointers:

When prosecuting patent applications, statements made during the examination process may be critical in ensuring an appropriate examination and scope of claims. Patent applicants should carefully review the prior art and only amend claims or make arguments that are necessary to appropriately distinguish their invention from the prior art. Applicants should consider separate claims for different embodiments disclosed in the specification to ensure that any disclaimer is not interpreted broadly to cover all claimed embodiments, as an alternative or in addition to a single claim covering multiple embodiments.

The practical effect of this decision is to warn patent owners that statements (and claim amendments) made during the examination process will be scrutinized later during litigation. Thus, any statements (or amendments) during prosecution need to be strategically constructed based on a well-informed understanding of the prior art.

Irah Donner is a partner in Manatt’s intellectual property practice and is the author of Patent Prosecution: Law, Practice, and Procedure, Eleventh Edition, and Constructing and Deconstructing Patents, Second Edition, both published by Bloomberg Law.

1 Genuine Enabling Tech. LLC v. Nintendo Co., 29 F.4th 1365, 2022 USPQ2d 305, 2022 WL 982246 (Fed. Cir. 2022).

2 Id., 29 F.4th at 1368 (quoting U.S. Patent No. 6,219,730, col. 1 ll. 14–18, col. 3 ll. 26–30).

3 Id., 29 F.4th at 1368 (quoting 6,219,730 patent, col. 1 ll. 14–18, col. 3 ll. 26–30).

4 Id., 29 F.4th at 1368–69 (citing 6,219,730 patent, col. 1 ll. 21–28).

5 Id., 29 F.4th at 1369 (citing 6,219,730 patent, col. 3 ll. 30–36).

6 Id., 29 F.4th at 1369 (citing 6,219,730 patent, col. 4 ll. 28–31).

7 Id., 29 F.4th at 1369 (citing 6,219,730 patent, col. 7 l. 61–col. 8 l.4).

8 Id., 29 F.4th at 1369 (citing 5,990,866 patent, col. 1 l. 66–col. 2 l.6).

9 Id., 29 F.4th at 1369 (citing 5,990,866 patent, col. 3 l. 64–col. 4 l.2).

10 Id., 29 F.4th at 1369 (citing 5,990,866 patent, col. 5 ll. 16–18).

11 Id., 29 F.4th at 1370 (emphasis by the court).

12 Id., 29 F.4th at 1371.

13 Id., 29 F.4th at 1371.

14 Id., 29 F.4th at 1371.

15 Id., 29 F.4th at 1373.

16 Id., 29 F.4th at 1373.

17 Id., 29 F.4th at 1373 (citing Mantech Env’t Corp. v. Hudson Env’t Servs., Inc., 152 F.3d 1368, 1373, 47 USPQ2d 1732, 1737 (Fed. Cir. 1998); and Vitronics Corp. v. Conceptronic, Inc., 90 F.3d 1576 , 1584, 39 USPQ2d 1572, 1578 (Fed. Cir. 1996)).

18 Id., 29 F.4th at 1373.

19 Id., 29 F.4th at 1374 (quoting Omega Eng’g, Inc., v. Raytek Corp., 334 F.3d 1314, 1325, 67 USPQ2d 1321, 1329 (Fed. Cir. 2003) (citations omitted)).

20 Id., 29 F.4th at 1374 (citing Tech. Props. Ltd. LLC v. Huawei Techs. Co., 849 F.3d 1349, 1358, 121 USPQ2d 1916, 1921 (Fed. Cir. 2017)).

21 Id., 29 F.4th at 1374–75 (citations omitted).

22 Id., 29 F.4th at 1375–76.

23 Id., 29 F.4th at 1375.



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