`Tel: 571-272-7822
`
`
`Paper 33
`Entered: October 22, 2018
`
`UNITED STATES PATENT AND TRADEMARK OFFICE
`____________
`
`BEFORE THE PATENT TRIAL AND APPEAL BOARD
`____________
`
`SAMSUNG ELECTRONICS CO., LTD.,
`Petitioner,
`
`v.
`
`PROMOS TECHNOLOGIES, INC.,
`Patent Owner.
`____________
`
`Case IPR2017-01412
`Patent 6,069,507
`____________
`
`
`Before JAMESON LEE, KEVIN F. TURNER, and
`JOHN A. HUDALLA, Administrative Patent Judges.
`
`LEE, Administrative Patent Judge.
`
`
`
`
`FINAL WRITTEN DECISION
`35 U.S.C. § 318(a)
`
`
`
`
`
`
`
`I.
`
`INTRODUCTION
`
`IPR2017-01412
`Patent 6,069,507
`
`
`
`A. Background and Summary
`Petitioner1 filed a Petition (Paper 1, “Pet.”) to institute inter partes
`review of claims 10, 11, 13, and 15 of U.S. Patent No. 6,069,507 (Ex. 1001,
`“the ’507 patent”). We instituted trial only as to claims 13 and 15 on the
`alleged ground of anticipation by Jefferson. 2 Paper 7. Subsequent to the
`Supreme Court’s decision in SAS Institute v. Iancu, 138 S. Ct. 1348 (2018),
`we instituted trial on the remaining claims and ground presented in the
`Petition. Paper 16. Thus, also included for trial are claims 10 and 11, on the
`alleged ground of obviousness over the combined teachings of Donnelly3
`and Iwamoto4.
`Prior to our adding claims 10 and 11 to the trial, Patent Owner5 filed a
`Patent Owner Response (“PO Resp.”) addressing only claims 13 and 15.
`Ordinarily, arguments in a Preliminary Response do not carry automatically
`over to the Patent Owner Response. However, after we added claims 10 and
`11 to the trial, we allowed Patent Owner to rely on its Preliminary Response
`(Paper 6) insofar as it addressed claims 10 and 11, and Patent Owner waived
`the opportunity to supplement its Patent Owner Response to address claims
`10 and 11. Paper 19. Petitioner filed a Reply addressing all challenged
`
`
`1 Samsung Electronics Co., Ltd.
`2 U.S. Patent No. 5,744,991.
`3 U.S. Patent No. 5,945,862.
`4 U.S. Patent No. 6,292,040 B1.
`5 ProMOS Technologies, Inc.
`
`2
`
`
`
`IPR2017-01412
`Patent 6,069,507
`claims and grounds. Paper 22 (“Reply”). Patent Owner filed a Sur-Reply.
`Paper 25 (“SR”).
`Oral argument was consolidated for IPR2017-01412 and IPR2017-
`01413, and held on June 21, 2018. A transcript of the consolidated oral
`argument has been entered as Paper 32.
`We find that Petitioner has shown by a preponderance of the evidence
`that each of claims 10, 11, 13, and 15 is unpatentable.
`B. Related Matters
`Both Petitioner and Patent Owner have identified the following action
`as involving the ’507 patent: ProMOS Technologies, Inc. v. Samsung
`Electronics Co., Ltd., No. 1:16-cv-00335-SLR (D. Del.). Pet. 1, Paper 5.
`Petitioner filed a second petition for inter partes review of the ’507 patent in
`IPR2017-01413. Petitioner further identifies these inter partes review
`proceedings between the parties that involve other patents: IPR2017-00032;
`IPR2017-00033; IPR2017-00035; IPR2017-00036; IPR2017-00037;
`IPR2017-00038; IPR2017-00039; and IPR2017-00040. Pet. 1–2. Patent
`Owner additionally identifies these inter partes review proceedings between
`the parties that involve other patents: IPR2017-01414, IPR2017-01415,
`IPR2017-01416, IPR2017-01417, IPR2017-01418, and IPR2017-01419.
`Paper 5.
` The ’507 Patent
`C.
`The ’507 patent relates to delay-locked loops (DLLs) and to reducing
`delay line length in DLLs. Ex. 1001, 1:7–9. The ’507 patent notes that in
`order to achieve sufficient coverage of frequency ranges and guarantee
`desired resolution, DLLs generally require long delay lines. Id. at 1:14–18.
`Figure 1 is reproduced below:
`
`3
`
`
`
`IPR2017-01412
`Patent 6,069,507
`
`
`Figure 1 illustrates a diagram of what the ’507 patent regards as typical
`digital DLL according to the prior art. Id. at 2:24.
`
`With respect to the prior art shown in Figure 1, input clock signal
`CLKIN is received at buffer 10 which provides a buffered clock signal CKI
`and which is coupled to phase detector 12, shift register 14, and delay line
`16. Id. at 1:20–23. Delay line 16 is coupled to buffer 18 through which an
`output clock signal, CLKOUT, is produced. Id. at 1:23–25. The CLKOUT
`signal passes through buffer 20 to produce a feedback clock signal, CKF, to
`phase detector 12. Id. at 1:25–27. Phase detector 12 determines whether a
`phase difference exists between the buffered input signal CKI and feedback
`clock signal CKF. Id. at 1:27–29. The phase difference determines an
`appropriate shift in the buffered input clock signal via adjustment of shift
`register 14 to select sufficient delay via delay line 16. Id. at 1:29–32.
`
`The ’507 patent explains that there are several disadvantages with
`prior art type DDLs as clock speeds continue to increase. Id. at 1:34–36. To
`achieve high resolution and coverage of wide frequency ranges, the delay
`cells in delay line 16 and associated register cells in shift register 14 increase
`in number. Id. at 1:37–40. That expansion in length of the delay line leads
`
`4
`
`
`
`IPR2017-01412
`Patent 6,069,507
`to larger silicon requirements and higher power consumption, as well as
`longer lock-in time and larger frequency signal distortion. Id. at 1:43–47.
`
`The ’507 patent aims to overcome these disadvantages via the
`following disclosed method:
`[A] method for reducing delay line length in a digital delay
`locked loop (DLL) includes determining a phase difference
`between an input clock signal and a feedback clock signal, and
`maintaining the phase difference between the input clock signal
`and the feedback clock signal within approximately 180◦. The
`method also includes delaying the input clock signal to
`compensate for the phase difference, wherein a number of delay
`cells utilized is reduced by approximately one-half.
`Id. at 2:3–11. In that regard, Figure 2 of the ’507 patent is reproduced below:
`
`
`Figure 2 illustrates a diagram of a DLL according to the ’507 patent. Id. at
`2:25–26. With respect to Figures 1 and 2, the ’507 patent states that like
`components have been similarly numbered in the two figures. Id. at 2:49–
`51. As compared to the DLL of the prior art described in the ’507 patent,
`DLL 24 in Figure 2 of the ’507 patent adds inverter 26, switch 28, and
`second phase detector 30. Id. at 2:55–57. According to the ’507 patent, the
`length of delay line 16' and the corresponding number of cells in shift
`
`5
`
`
`
`IPR2017-01412
`Patent 6,069,507
`register 14' are reduced as compared to the prior art DLL. Id. at 2:57–60.
`Operation of DLL 24 in Figure 2 is described as follows:
`
`In operation, the second phase detector 30 preferably
`controls the course of the buffered input clock signal CKI by
`controlling the selection of the switch 28. When the second
`phase detector 30 determines that the feedback clock signal CKF
`from the DLL 24 is behind the buffered input clock CKI within
`a 180◦ phase difference, the second phase detector 30 controls the
`switch 28 to be at position (1). The inverter 26 is thus bypassed,
`and the operation of DLL 24 proceeds in a typical manner as
`described with reference to FIG. 1. With the second phase
`detector 30 determining that CKF was within 180◦ behind CKI,
`the delay line 16' is required to compensate for a less than 180◦
`phase difference after the DLL 24 gets locked by the feedback
`through phase detector 12.
`
`When the second phase detector 30 determines that CKF
`is more than 180◦ behind CKI, the second phase detector 30
`controls switch 28 to be at position (2). The inverted buffered
`clock signal is thus selected, so that the input clock signal CKI is
`reversed by 180◦[.] Through the inversion, the phase difference
`needing to be compensated by the delay line 16' is made less than
`180◦ and within the normal operation capabilities of the phase
`adjusting loop formed by phase detector 12, shift register 14', and
`delay line 16'.
`Id. at 2:61–3:15. According to the ’507 patent, DLL 24 as described above
`“requires approximately one-half the length that a typical DLL would require
`for comparable clock deskewing needs.” Id. at 3:16–19.
`
`Of all challenged claims, claims 10 and 13 are independent and are
`reproduced below:
`
`10. A method for reducing delay line length in a
`digital delay locked loop (DLL), the method comprising:
`determining a phase difference between an input clock signal
`and a feedback clock signal;
`
`6
`
`
`
`IPR2017-01412
`Patent 6,069,507
`maintaining the phase difference between the input clock
`signal and the feedback clock signal [within6]
`approximately 180◦, including adjusting the input clock
`signal with a loop comprising a phase detector, shift
`register, and delay line when the determined phase
`difference is less than approximately 180◦; and
`delaying the input clock signal to compensate for the phase
`difference, wherein a number of delay cells utilized is
`reduced by approximately one-half.
`13. A method for reducing delay line length in a digital
`
`delay lock look (DLL), the method comprising:
`determining whether a feedback clock signal in the DLL follows
`within a 180◦ phase difference behind an input clock signal;
`and
`selecting a switch position according to the determining step,
`including selecting a first switch position when the feedback
`clock signal follows behind the input clock signal with[in7]
`180◦.
`
`
`6 Based on an apparent error, the word “within” is missing from the
`maintaining clause as it appears in the published version of claim 10.
`During prosecution, Applicant amended the language of what became
`claim 10 to include, inter alia, the limitation “within approximately 180◦.”
`Ex. 1004, 58, 59. In the Notice of Allowance, the Examiner also
`acknowledged that the maintaining step recites “within approximately 180
`degree[s].” Id. at 65. As indicated in our institution decision, we read claim
`10 as including “within.” Paper 7, 6 n. 3. Neither party contested this
`reading in subsequent papers.
`7 The word “with” in the selecting clause evidently reflects a publishing
`error, and so we read it as the different word “within.” During prosecution,
`the language of what became claim 13 recited the following limitation:
`“selecting a switch position according to the determining step,” including
`“selecting a first switch position when the feedback clock signal follows
`behind the input clock signal within 180◦.” Ex. 1004, 27–28, 59 (emphasis
`added). The Examiner also used the word “within” when stating the reasons
`for allowing this claim. Id. at 65. As indicated in our institution decision,
`
`7
`
`
`
`IPR2017-01412
`Patent 6,069,507
`Ex. 1001, 4:47–59; 4:66–5:7.
`Evidence Relied Upon by Petitioner
`D.
`Petitioner relies on the following references8:
`
`
`
`Reference
`Donnelly U.S. Pat. No. 5,945,862
`
`Iwamoto U.S. Pat. No. 6,292,040 B1
`
`Jefferson U.S. Pat. No. 5,744,991
`
`Date
`Aug. 31, 1999,
`Filed July 31, 1997
`Sept. 18, 2001,
`Filed March 25, 1998
`Apr. 28, 1998,
`Filed Oct. 16, 1995
`
`Exhibit
`Ex. 1005
`
`Ex. 1006
`
`Ex. 1007
`
`
`Petitioner also relies on the Declaration of Jacob Baker, Ph.D., P.E.
`(Ex. 1002).
`The Instituted Grounds
`E.
`We instituted trial on the following grounds of unpatentability (Paper
`7, 35; Paper 16, 2):
`Claim(s) Challenged
`10 and 11
`
`Basis
`§ 103(a)
`
`References
`Donnelly and Iwamoto
`
`A.
`
`13 and 15
`
`§ 102(a) and § 102(e) Jefferson
`
`ANALYSIS
`II.
`The Law on Anticipation and Obviousness
`To establish anticipation, each and every element in a claim, arranged
`as recited in the claim, must be found in a single prior art reference.
`Net MoneyIN, Inc. v. VeriSign, Inc., 545 F.3d 1359, 1369 (Fed. Cir. 2008);
`
`we read claim 13 as including “within.” Paper 7, 6 n. 4. Neither party
`contested this reading in subsequent papers.
`8 The ’507 patent was filed on May 22, 1998 and does not claim priority to
`any earlier application. Ex. 1001, [22].
`
`8
`
`
`
`IPR2017-01412
`Patent 6,069,507
`Karsten Mfg. Corp. v. Cleveland Golf Co., 242 F.3d 1376, 1383 (Fed. Cir.
`2001). While the elements must be arranged in the same way as is recited in
`the claim, “the reference need not satisfy an ipsissimis verbis test.” In re
`Gleave, 560 F.3d 1331, 1334 (Fed. Cir. 2009); In re Bond, 910 F.2d 831,
`832–33 (Fed. Cir. 1990). Identity of terminology between the anticipatory
`prior art reference and the claim is not required. “A reference anticipates a
`claim if it discloses the claimed invention ‘such that a skilled artisan could
`take its teachings in combination with his own knowledge of the particular
`art and be in possession of the invention.’” In re Graves, 69 F.3d 1147,
`1152 (Fed. Cir. 1995). Prior art references must be “considered together
`with the knowledge of one of ordinary skill in the pertinent art.” In re
`Paulsen, 30 F.3d 1475, 1480 (Fed. Cir. 1994).
`Also, “it is proper to take into account not only specific teachings of
`the reference but also the inferences which one skilled in the art would
`reasonably be expected to draw therefrom.” In re Preda, 401 F.2d 825, 826
`(CCPA 1968). As the Court of Appeals for the Federal Circuit recently
`explained, the dispositive question for anticipation is whether one skilled in
`the art would reasonably understand or infer from a prior art reference that
`every claim element is disclosed in that reference. Eli Lilly & Co. v. L.A.
`Biomedical Research Inst., 849 F.3d 1073, 1074–1075 (Fed. Cir. 2017).
`The question of obviousness is resolved on the basis of underlying
`factual determinations including: (1) the scope and content of the prior art;
`(2) any differences between the claimed subject matter and the prior art;
`(3) the level of ordinary skill in the art; and (4) objective evidence of
`nonobviousness. Graham v. John Deere Co., 383 U.S. 1, 17–18 (1966).
`One seeking to establish obviousness based on more than one reference also
`
`9
`
`
`
`IPR2017-01412
`Patent 6,069,507
`must articulate sufficient reasoning with rational underpinning to combine
`teachings. See KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 418 (2007).
`Level of Ordinary Skill in the Art
`B.
`Petitioner proposes that a person of ordinary skill in the art at the time
`of the alleged invention of the ’507 patent “would have had at least a
`bachelor’s degree in electrical engineering or a similar field, and at least two
`to three years of experience in integrated circuit design. (Ex. 1002, ¶¶ 18–
`19.)” Pet. 5 (footnote omitted). Patent Owner has not expressed what
`constitutes the level of ordinary skill in the art. We find Petitioner’s
`proposal vague insofar as it includes the qualifier “at least” to describe the
`level of education and the amount of working experience. This qualifier
`results in ranges that are too broad to provide a meaningful indication of
`what knowledge and skills would have been possessed by one of ordinary
`skill in the art. We adopt the level of skill in the art proposed by Petitioner,
`as we credit the testimony of Petitioner’s declarant in that regard (Ex. 1002
`¶ 18), but eliminate the qualifier “at least” to eliminate vagueness.
`
`C. Claim Construction
`Petitioner contends that the expiration date of the ’507 patent is May
`22, 2018. Pet. 17. Patent Owner does not dispute that expiration date. PO
`Resp. 5. Thus, the ’507 patent has expired, and we construe the challenged
`claims according to rules applicable to expired patent claims.
`We review expired patent claims according to the standard applied by
`the district courts. See In re Rambus, 694 F.3d 42, 46 (Fed. Cir. 2012).
`Specifically, we apply the principles set forth in Phillips v. AWH Corp.,
`415 F.3d 1303, 1312 (Fed. Cir. 2005) (en banc). Patent Owner agrees that
`the claim construction principles set forth in Phillips apply. PO Resp. 5. “In
`
`10
`
`
`
`IPR2017-01412
`Patent 6,069,507
`determining the meaning of the disputed claim limitation, we look
`principally to the intrinsic evidence of record, examining the claim language
`itself, the written description, and the prosecution history, if in evidence.”
`DePuy Spine, Inc. v. Medtronic Sofamor Danek, Inc., 469 F.3d 1005, 1014
`(Fed. Cir. 2006) (citing Phillips, 415 F.3d at 1312–17). However, claim
`construction does not mean importing limitations into the claims in the name
`of construction, if the limitations are not otherwise there. As the Federal
`Circuit explained in Phillips,
`
`It is a “bedrock principle” of patent law that “the claims of
`a patent define the invention to which the patentee is entitled the
`right to exclude.” Innova, 381 F.3d at 1115; see also Vitrionics,
`90 F.3d at 1582 (“we look to the words of the claims themselves
`. . . to define the scope of the patented invention”); Markman, 52
`F.3d at 980 (“The written description part of the specification
`itself does not delimit the right to exclude. That is the function
`and purpose of claims.”). That principle has been recognized
`since at least 1936, when Congress first required that the
`specification include a potion in which the inventor “shall
`particularly specify and point out the part, improvement, or
`combination, which he claims as his own invention or
`discovery.” Act of July 4, 1836, ch. 357, § 6, 5 Stat. 117, 119.
`In the following years, the Supreme Court made clear that the
`claims are “of primary importance, in the effort to ascertain
`precisely what it is that is patented.” Merrill v. Yeomans, 94 U.S.
`568, 570, 24 L.Ed. 235 (1876). Because the patentee is required
`to “define precisely what his invention is,” the Court explained,
`it is “unjust to the public, as well as an evasion of the law, to
`construe it in a manner different from the plain import of its
`terms.” White v. Dunbar, 119 U.S. 47, 52, 7 S.Ct. 72, 30 L.Ed.
`303 (1886); see also Cont’l Paper Bag Co. v. E. Paper Bag Co.,
`210 U.S. 405, 419, 28 S.Ct. 748, 52 L.Ed. 1122 (1908) (“the
`claims measure the invention”); McCarty v. Lehigh Valley R.R.
`Co., 160 U.S. 110, 116, 16 S.Ct. 240, 40 L.Ed. 358 (1895) (“if
`we once begin to include elements not mentioned in the claim, in
`order to limit such claim . . ., we should never know where to
`stop”); Aro Mfg. Co. v. Convertible Top Replacement Co., 365
`
`11
`
`
`
`IPR2017-01412
`Patent 6,069,507
`U.S. 336, 339, 81 S.Ct. 599, 5 L.Ed.2d 592 (1961) (“the claims
`made in the patent are the sole measure of the grant”).
`Phillips, 415 F.3d at 1312.
`Claim terms generally are given their ordinary and customary
`meaning, as understood by one of ordinary skill in the art when read in the
`context of the specification and prosecution history. Thorner v. Sony
`Comput. Entm’t Am. LLC, 669 F.3d 1362, 1365 (Fed. Cir. 2012) (citing
`Phillips, 415 F.3d at 1313). There are two exceptions to that rule: “1) when
`a patentee sets out a definition and acts as his own lexicographer,” and
`“2) when the patentee disavows the full scope of a claim term either in the
`specification or during prosecution.” Thorner, 669 F.3d at 1365.
`It is likewise not enough [for disavowal] that the only
`embodiments, or all of the embodiments, contain a particular
`limitation. We do not read limitations from the specification into
`claims; we do not redefine words. Only the patentee can do that.
`To constitute disclaimer, there must be clear and unmistakable
`disclaimer.
`Id. at 1366–67. See also EPOS Techs. Ltd. v. Pegasus Techs. Ltd., 766 F.3d
`1338, 1341 (Fed. Cir. 2014).
`Disavowal can be effectuated by language in the specification or the
`prosecution history. Poly-America, L.P. v. API Indus., Inc., 839 F.3d 1131,
`1136 (Fed. Cir. 2016). “In either case, the standard for disavowal is
`exacting, requiring clear and unequivocal evidence that the claimed
`invention includes or does not include a particular feature.” Id.
`
`If an inventor acts as his or her own lexicographer, the definition must
`be set forth in the specification with reasonable clarity, deliberateness, and
`
`
`
`12
`
`
`
`IPR2017-01412
`Patent 6,069,507
`precision. 9 Renishaw PLC v. Marposs Societa’ per Azioni, 158 F.3d 1243,
`1249 (Fed. Cir. 1998). Also, “the claims must ‘not be read restrictively
`unless the patentee has demonstrated a clear intention to limit the claim
`scope using words or expressions of manifest exclusion or restriction.’”
`Williamson v. Citrix Online, LLC, 792 F.3d 1339, 1347 (Fed. Cir. 2015)
`(internal quotation omitted).
`If the words of the claim are clear, and absent the exceptions above,
`the claims should be interpreted as written and not rewritten in the name of
`claim construction. SRAM Corp. v. AD-II Engineering Inc., 465 F.3d 1351,
`1359 (Fed. Cir. 2006). In SRAM Corp., the Federal Circuit stated:
`While SRAM strongly urges the court to interpret the claim to
`encompass the innovative precision indexing shifting feature it
`contends it has invented, we are powerless to rewrite the claims
`and must construe the language of the claim at issue based on the
`words used. Hoganas AB v. Dresser Indus., Inc., 9 F.3d 948, 951
`(Fed. Cir. 1993). In this case, the words are clear and the claims
`cover no more than the recited method of taking up lost motion
`and effecting a shift.
`SRAM Corp., 465 F.3d at 1359 (emphasis added); see K-2 Corp. v. Solomon
`S.A., 191 F.3d 1356, 1364 (Fed. Cir. 1999) (“Courts do not rewrite claims;
`instead, we give effect to the terms chosen by the patentee.”).
`Only terms which are in controversy need to be construed, and only to
`the extent necessary to resolve the controversy. See Wellman, Inc. v.
`Eastman Chem. Co., 642 F.3d 1355, 1361 (Fed. Cir. 2011); Vivid Techs.,
`Inc. v. Am. Sci. & Eng’g, Inc., 200 F.3d 795, 803 (Fed. Cir. 1999).
`
`
`
`
`9 Neither party contends that the Specification of the ’507 patent specially
`defined any term or that the inventors of the ’507 acted as their own
`lexicographer. We have no reason to determine otherwise.
`
`13
`
`
`
`IPR2017-01412
`Patent 6,069,507
`
`1.
`“maintaining the phase difference between
`the input clock signal and the feedback clock signal
`[within] approximately 180◦”
`Claim 10 includes a step of “maintaining the phase difference between
`the input clock signal and the feedback clock signal [within] approximately
`180◦.” Ex. 1001, 4:51–53. In our institution decision, we construed this
`phrase to mean “ensuring that the feedback clock signal follows behind the
`input clock signal by less than approximately 180◦.” Paper 7, 10–13. We
`have reconsidered our initial construction in light of the entire trial record.
`The “maintaining . . . [within] approximately 180◦” recitation does not
`specify whether the input clock signal must be ahead of the feedback clock
`signal or the feedback clock signal must be ahead of the input clock signal.
`Without that restrictive recitation, either signal can be ahead of the other by
`within approximately 180◦, and either signal can lag the other by within
`approximately 180◦. That is how Petitioner has treated the limitation, i.e.,
`that the within approximately 180◦ separation can be in either direction.
`Pet. 29–33; Reply 15.
`
`That position is significant in this case, because there exist two
`different ways of looking at a phase lead or a phase lag. Petitioner’s
`declarant, Dr. Baker, explains,
`A person of ordinary skill in the art would have understood that
`for two clock signals having the same frequency, and hence the
`same period, the phase difference between the two signals is
`always within approximately 180◦. For example, if the
`feedback clock signal is lagging the input clock signal by 210◦,
`that is the same as the feedback clock signal leading the clock
`signal by 150◦.
`Ex. 1002 ¶ 97. From that perspective, for signals that have the same
`frequency and period, a particular phase lag is the same as a phase
`
`14
`
`
`
`IPR2017-01412
`Patent 6,069,507
`lead of an amount that is the 360◦ complement (difference from 360◦)
`of the phase lag. Petitioner contends the limitation at issue is always
`satisfied by two clock signals having the same frequency and period
`in a system, because the 180◦ difference required by the limitation can
`be in either direction. Pet. 33 (citing Ex. 1002 ¶ 97).
`Patent Owner does not dispute Petitioner’s assertion that if the 180◦
`
`difference required by the limitation can be in either direction, then the
`limitation always is satisfied by an input clock signal and a feedback clock
`signal that have the same frequency and period. Patent Owner, however,
`argues that a reading of the limitation covering a variation in either direction
`is inconsistent with the intrinsic record, i.e., the Specification and the
`prosecution history, and would, in effect, read the limitation out of the claim
`and render it meaningless. Prelim. Resp. 6–7. In essence, Patent Owner
`notes that a feedback clock signal is always either within 180◦ behind the
`input clock signal or within 180◦ ahead of the input clock signal, without
`exception. According to the Patent Owner, the limitation “maintaining the
`phase difference between the input clock signal and the feedback clock
`signal [within] approximately 180◦” should be construed as meaning
`“ensuring that the feedback clock signal follows behind the input clock
`signal by less than 180◦.” Id. at 8 (emphasis added).
`
`In the Decision on Institution, we determined that the above-noted
`arguments of Patent Owner were persuasive. Paper 7, 11. However, initial
`claim construction made at the time of institution of trial is not conclusive
`and does not carry over necessarily to a Final Written Decision. Here, we
`must reassess the issue on the basis of the complete record developed during
`trial and also on a fresh review of the applicable binding case authority
`
`15
`
`
`
`IPR2017-01412
`Patent 6,069,507
`governing the law on claim interpretation. Based on the complete trial
`record, Patent Owner’s arguments are not persuasive.
`Subsequent to institution of trial, Petitioner submitted a Reply.
`Paper 22. It identifies and addresses numerous factors, all discussed below,
`that weigh in favor of Petitioner’s claim construction, including (1) that we
`must respect the language of the claims in the absence of clear disavowal,
`Reply 15; (2) that the record does not support Patent Owner’s contention
`that under Petitioner’s broader construction, the limitation at issue is
`superfluous or meaningless, Reply 17–18; (3) that the prosecution history
`does not support an express disavowal by the patent applicant during pre-
`issuance examination, Reply 23–25; and (4) that the Specification of the
`’507 patent demonstrates the patent drafter knew how to describe the
`relationship between two clock signals in a manner that makes clear which
`clock signal leads or lags the other in phase via express recitations with the
`words “behind” or “follows.” Reply 19–20.
`
`Patent Owner relies on general principles that urge in favor of “giving
`effect to all terms in the claim” and avoid rendering claim language
`“functionally meaningless.” Prelim. Resp. 6. Those principles do not
`override the bedrock principle of patent law, explained in Phillips, that it is a
`claim that defines the covered invention and that it is “unjust to the public,
`as well as an evasion of the law, to construe it in a manner different from the
`plain import of its terms.” Phillips, 415 F.3d at 1312; see McCarty,
`160 U.S. at 116 (“[I]f we once begin to include elements not mentioned in
`the claim, in order to limit such claim . . ., we should never know where to
`stop.”). We must not, if the words of the claim are clear and if there is no
`disavowal, rewrite a claim in the name of claim construction. SRAM Corp.,
`
`16
`
`
`
`IPR2017-01412
`Patent 6,069,507
`465 F.3d at 1359; see also K-2 Corp., 191 F.3d at 1364. This is such a case.
`We must not rewrite the claims.
`
`The words of the claim are clear in not specifying which signal leads
`or lags, and there is no express disavowal by Patent Owner, either in the
`Specification or in the prosecution history, as will be explained below. We
`must not rewrite the claim to add the requirement proposed by Patent
`Owner.
`The Specification of the ’507 patent describes,
`When the second phase detector 30 determines that CKF
`[feedback clock signal] is more than 180◦ behind CKI [input
`clock signal], the second phase detector 30 controls switch 28 to
`be at position (2). The inverted buffered clock signal is thus
`selected, so that the input clock signal CKI is reversed by 180◦[.]
`Through the inversion, the phase difference needing to be
`compensated by the delay line 16' is made less than 180◦ and
`within the normal operation capabilities of the phase adjusting
`loop formed by phase detector 12, shift register 14', and delay
`line 16'.
`Ex. 1001, 3:7–15. 10 The above-quoted description constitutes an affirmative
`disclosure of one embodiment, and not a disavowal of anything that is
`different. Elsewhere in the Specification, there also is no clear language of
`disavowal.
`
`
`10 According to Petitioner, even this disclosed embodiment of the
`’507 patent does not ensure that the feedback clock signal follows behind the
`input clock signal by less than 180◦, because in some instances, the switch
`continuously toggles between position (1) and position (2). Reply 20–23.
`We do not reach that issue because Petitioner would still prevail even
`assuming that the sole embodiment disclosed in the Specification of the
`’507 patent ensures that the feedback clock signal follows behind the input
`clock signal by less than 180◦.
`
`17
`
`
`
`IPR2017-01412
`Patent 6,069,507
`
`Also, as noted by Petitioner (Reply 19–20), the Specification of the
`’507 patent demonstrates that the patent drafter knew how to describe the
`relationship between two clock signals in a manner that makes clear which
`clock signal leads or lags the other in phase, by using the word “behind” to
`indicate which signal lags the other. Ex. 1001, 2:63–66; 3:3–4; 3:8–9.
`Similarly, claim 13 recites “determining whether a feedback clock signal in
`the DLL follows within a 180◦ phase difference behind an input clock
`signal.” Id. at 5:1–3 (emphases added). By not rewriting the claim, we give
`effect to the words chosen by the applicant for patent in drafting the claims.
`If they are so broad as to be functionally meaningless, they still are what the
`claim drafter has recited and Patent Owner could have sought correction
`during the pendency of the patent, e.g., seeking to reissue the patent claim.
`
`With regard to the prosecution history, it is anything but clear even as
`presented by Patent Owner. Patent Owner’s articulation is this:
`[T]he prosecution history makes clear that this limitation must be
`given meaning, and that it was important to the issuance of the
`patent over the art of record. During prosecution, claims that
`lacked this limitation were rejected as obvious over Butcher
`which, among other things, disclosed a system that included two
`clocks having the same frequency (and thus the same period).
`Ex. 1004 (’507 file history) at 45; Ex. 2001 (Butcher) at col. 4:9–
`16. Claim 11, which issued as claim 10, included the language
`being construed here, and was identified as allowable over the
`art of record. Ex. 1004 (’507 file history) at 65. Once the claim
`was amended to include the limitation “maintaining the phase
`difference between an input clock signal and a feedback clock
`signal [within] approximately 180 degree” it was allowed, and
`the Notice of Allowance stated: “As to claims 9, 11, and 15
`[which issued as claims 8, 10 and 13], none of the prior art
`teaches the limitation “maintaining the phase difference between
`an input clock signal and a feedback clock signal within
`approximately 180 degree.” Id.
`
`18
`
`
`
`IPR2017-01412
`Patent 6,069,507
`Prelim. Resp. 7–8.
`
`The above description by Patent Owner is internally inconsistent and
`self-contradictory. First, Patent Owner asserts that application claim 11,
`which issued as patent claim 10, already “included the language being
`construed here, and was identified as being allowable over the art of record.”
`Id. at 7. Then, Patent Owner states: “Once [application claim 11] was
`amended to include the limitation ‘maintaining the phase difference between
`an input clock signal and a feedback clock signal [within] approximately 180
`degree’ it was allowed.” Id. Patent Owner’s suggestion that application
`claim 11 was amended to overcome a prior art rejection cannot be correct if
`it was allowable prior to the amendment.