  United States Court of Appeals
      for the Federal Circuit
              __________________________

            WOODROW WOODS AND
        MARINE EXHAUST SYSTEMS, INC.,
               Plaintiffs-Appellees,

                           v.
       DEANGELO MARINE EXHAUST, INC.,
             Defendant-Appellant.
              __________________________

                      2010-1478
              __________________________

   Appeal from the United States District Court for the
Southern District of Florida in No. 08-CV-81579, Judge
Daniel T.K. Hurley.
              __________________________

               Decided: August 28, 2012
              __________________________

     DENISE J. BLEAU, Ward, Damon, Posner, Pheterson &
Bleau, PL, of West Palm Beach, Florida, argued for plain-
tiffs-appellees. Of counsel was MARK D. BOWEN, Malin
Haley DiMaggio Bowen & Lhota, P.A., of Fort Lauder-
dale, Florida.

    MICHAEL C. CESARANO, Feldman Gale, P.A., of Miami,
Florida, argued for defendant-appellant. With him on the
brief was RICHARD GUERRA.
               __________________________
2                               WOODS v. DEANGELO MARINE

        Before LINN, DYK, and REYNA, Circuit Judges.
LINN, Circuit Judge.

     DeAngelo Marine Exhaust, Inc. (“DeAngelo”) appeals
from the denial by the United States District Court for
the Southern District of Florida of DeAngelo’s motion for
judgment as a matter of law (“JMOL”) as to invalidity and
infringement of U.S. Patents No. 5,740,670 (“’670 Patent”)
and No. 6,035,633 (“’633 Patent”) owned by Woodrow
Woods (“Woods”) and exclusively licensed to Marine
Exhaust Systems, Inc. (“MES”) following a jury verdict in
MES’s favor. DeAngelo also appeals the district court’s
evidentiary ruling and claim construction underlying the
jury verdict and the denial of DeAngelo’s motion to sanc-
tion MES for failing to conduct an adequate pre-filing
investigation. For the reasons set forth below, this court
affirms.

                       I. BACKGROUND

                 A. The Patents in Suit

    Water jacketed marine exhaust systems cool exhaust
as it exits the engine of a marine vessel. These devices
generally consist of two metal cylinders with exhaust
flowing through the inner cylinder and water flowing
through the space between the inner and outer cylinders.
The patents in suit are directed to an apparatus that
more efficiently cools exhaust by tapering the tail end of
the outer liner so it directs the cooling water into the
exhaust stream, and prevents water migration and corro-
sion by tapering the tail end of the inner liner to reduce
the turbulence at the end of the pipe.

     Woods filed U.S. Patent Application No. 08/419,097
(“’097 Application”) on April 10, 1995. The ’097 Applica-
tion disclosed and claimed: (1) a water jacketed exhaust
system with an elongated, tapered, inner liner and outer
WOODS   v. DEANGELO MARINE                              3
shell; (2) a spacer separating the liner and shell; and (3)
the inner and outer tapered surfaces acting as a clip for
turbulence and a deflection surface respectively. See, e.g.,
’097 Application claim 1. On December 29, 1995, Woods
filed U.S. Patent Application No. 08/580,548 (“’548 Appli-
cation”) as a continuation-in-part (“CIP”) of the ’097
Application. The ’548 Application’s claims were broader
than the ’097 Application’s claims. For example, claim 1
of the ’548 Application required extension of the inner
liner beyond the outer shell, but did not limit the tapered
surfaces to deflecting water and clipping turbulence.
Compare ’097 Application claim 1, with ’548 Application
claim 1.

    On July 1, 1996, an examiner rejected all claims of the
’097 Application as anticipated by U.S. Patents No.
5,212,949 (“Shiozawa”) and No. 799,013 (“Moffitt”).
Instead of responding to the ’097 anticipation rejection,
Woods allowed the ’097 Application to go abandoned and
continued to prosecute the CIP ’548 Application. On April
25, 1997, the same examiner who had rejected the ’097
Application allowed several of the claims in the ’548
Application. On April 21, 1998, the ’548 Application
issued as the ’670 Patent.

    On December 15, 1997, before the ’548 Application
had matured into the ’670 Patent, Woods filed CIP appli-
cation No. 08/990,821 (“’821 Application”). The invention
claimed in the ’821 Application was similar to that of the
’548 Application, but was not limited to an elongated
inner liner extending beyond the outer shell. On April 1,
1999, the examiner rejected claims 1-4, 6, and 8-21 of the
’821 Application as anticipated by U.S. Patent No.
4,977,741 (“Lulloff”). Woods amended the claims by
reciting a spacer between the inner and outer cylinders
that created a back pressure so that water forcefully
sprayed out of a spray ring. Woods argued that Lulloff
did not contain this limitation and that the amended
4                                WOODS v. DEANGELO MARINE

claims were not anticipated. Woods never argued that the
claims were or were not patentable as initially written.
The examiner allowed the amended claims, and the ’821
Application issued as the ’633 Patent on March 14, 2000.
Woods exclusively licensed both the ’670 and ’633 Patents
to MES.

                B. Pre-Suit Investigation

     MES competes with DeAngelo in the marine exhaust
system market. Sometime prior to March 2006, other
members of the industry informed MES that DeAngelo
was selling exhaust systems that were believed to infringe
the Woods patents. Based on these statements, on March
10, 2006, MES wrote a letter to DeAngelo requesting
information on its water cooled products. DeAngelo
indicated in an April 3, 2006 response that it would
investigate MES’s infringement concerns and contact
MES. DeAngelo never contacted MES after sending its
initial April 3, 2006 letter. Over a year later one of MES’s
employees photographed an allegedly infringing DeAngelo
device on a vessel in West Palm Beach, FL. A year after
that, Sheila Prieschl, Vice President of MES, personally
inspected and photographed additional DeAngelo devices.
On December 31, 2008, after reviewing these photo-
graphs, MES and Woods filed this patent infringement
suit in the United States District Court for the Southern
District of Florida.

                C. The Proceedings Below

    Woods’s suit alleged that DeAngelo infringed one or
more claims of the ’670 or ’633 Patents and sought both
damages and injunctive relief. DeAngelo responded that
it did not infringe the Woods patents and that the as-
serted claims are invalid as obvious under 35 U.S.C.
§ 103. The case moved forward with discovery set to close
on February 9, 2010.
WOODS   v. DEANGELO MARINE                               5
    From the record it appears that on May 15, 2009,
MES propounded Interrogatory 25, which read: “State
with specificity all prior art that anticipates such claims
of one or more of the patents at issue or renders them
obvious. In doing so, specify the particular claim being
referred to and identify why such prior art anticipates
such claims or renders them obvious.” Pl.’s Mot. to Strike
and/or Exclude Evidence of Prior Art not Disclosed in
Disc., Ex. A, Woods v. DeAngelo Marine Exhaust, Inc., No.
08-cv-81579 (S.D. Fla. Apr. 11, 2010), ECF No. 177-1
(“Mot. to Strike Drawings”). It appears that DeAngelo
timely responded in mid-June that “[the] interrogatory
seeks attorney work-product information, and is not
discoverable. DeAngelo has not yet decided which prior
art references it will use to challenge the validity of the
patents in suit . . . [they] shall be disclosed as required by
35 U.S.C. § 282.” Id.

    On February 8, 2010, the day before discovery closed,
DeAngelo located several engineering drawings that
allegedly predated the ’670 and ’633 Patents. DeAngelo
immediately forwarded the drawings to MES with a letter
stating that “[t]hese documents arguably may anticipate
the Woods invention(s), or may be relied upon as showing
the state of the art in the early 1990’s.” E-mail from
Michael C. Cesarano, counsel for DeAngelo, to Jennifer
Simpson, counsel for MES (Feb. 8, 2010) (J.A. 293) (“Dis-
closure E-mail”). DeAngelo’s letter questioned “whether
[MES] would object to [DeAngelo’s] use of [the newly
discovered drawings] if trial should begin before March
10,” because DeAngelo’s disclosure would then violate 35
U.S.C. § 282. Id. It appears that MES did not object at
that time. Oral Arg. at 17:10-18:25, available at http://
www.cafc.uscourts.gov/oral-argument-recordings/all/
woods.html. On February 12, 2010, the parties submitted
their joint pretrial stipulation and included their exhibit
and witness lists. DeAngelo’s exhibit list included Exhibit
38: “Prior art drawings of Deangelo Marine Exhaust
6                                 WOODS v. DEANGELO MARINE

risers and diffusers.” Def.’s Ex. and Witness List, Woods
v. DeAngelo Marine Exhaust, Inc., No. 08-cv-81579 (S.D.
Fla. Feb. 12, 2010), ECF No. 105-2. These were the
drawings found on February 8, 2010. On February 24,
2010, DeAngelo alleged that MES and Woods failed to
conduct an adequate pre-filing investigation and moved
for sanctions under Rule 11 of the Federal Rules of Civil
Procedure.

    A two-week jury trial commenced on April 5, 2010. At
the beginning of DeAngelo’s defense, MES moved under
Federal Rules of Civil Procedure 26 and 37 to strike the
drawings DeAngelo had found on February 8, 2010. See
Mot. to Strike Drawings. MES argued that because
DeAngelo had failed to adequately supplement Interroga-
tory 25 with information about these drawings, they were
not properly identified prior to the close of discovery and
should be excluded. The district court found a violation of
Rule 26(e), ruling that:

    a party confronted with interrogatory [sic] of that
    nature has some obligation to move forward with
    the development of its defense and in a timely
    fashion to respond and supplement to its an-
    swer. . . . [T]o wait to do that until February 8th of
    2010 is not responsible. . . . [T]his is not a timely
    response and it is not a timely supplement to the
    propounded interrogatory. It is not a timely sup-
    plement to the answer that was [originally] given .
    . . its timing is way off, it should have done that
    much earlier.

Tr. of Prior Art Argument at 23-25, Woods v. DeAngelo
Marine Exhaust, Inc., No. 08-cv-81579 (S.D. Fla. Sept. 12,
2010), ECF No. 284 (“Prior Art Argument”) (emphasis
added) (paragraph structure not indicated). The court
then found DeAngelo’s untimely disclosure neither justi-
fied nor harmless and excluded the drawings pursuant to
WOODS   v. DEANGELO MARINE                               7
Federal Rule of Civil Procedure 37(c)(1). The jury found
Woods’s patents valid and infringed and DeAngelo re-
newed its motions for JMOL on validity and infringement.
On June 3, 2010, the court denied DeAngelo’s motions for
JMOL and for sanctions against Woods and MES. DeAn-
gelo timely appealed and alleges five errors by the district
court: (1) the exclusion of its drawings; (2) the district
court’s claim construction; (3) denial of JMOL as to valid-
ity; (4) denial of JMOL as to non-infringement; and (5)
denial of its motion to impose Rule 11 sanctions. This
court has jurisdiction pursuant to 28 U.S.C. § 1295(a)(1).

                      II. DISCUSSION

                  A. Standard of Review

     A district court’s evidentiary rulings are procedural in
nature and this court reviews them under the law of the
regional circuit, in this case, the Eleventh Circuit.
TransCore, LP v. Elec. Transaction Consultants Corp.,
563 F.3d 1271, 1277 (Fed. Cir. 2009). The Eleventh
Circuit reviews a district court’s evidentiary rulings for an
abuse of discretion. Goodman-Gable-Gould Co. v. Tiara
Condo. Ass’n, 595 F.3d 1203, 1210 (11th Cir. 2010). “‘A
district court abuses its discretion when it misapplies the
law in reaching its decision or bases its decision on find-
ings of fact that are clearly erroneous.’” Id. (quoting Acre
v. Garcia, 434 F.3d 1254, 1260 (11th Cir. 2006)). A dis-
trict court’s Rule 11 determination is also a matter of
regional circuit law that this court reviews for an abuse of
discretion under the regional circuit’s standard. Carter v.
ALK Holdings, Inc., 605 F.3d 1319, 1323 (Fed. Cir. 2010).
But if a procedural “issue pertains to or is unique to
patent law,” this court applies the law of the Federal
Circuit. O2 Micro Int’l Ltd. v. Monolithic Power Sys., 467
F.3d 1355, 1364 (Fed. Cir. 2006) (citing Sulzer Textil A.G.
v. Picanol N.V., 358 F.3d 1356, 1363 (Fed. Cir. 2004)).
8                                WOODS v. DEANGELO MARINE

     A district court’s construction of disputed claim terms
is a legal determination this court reviews de novo. Cybor
Corp. v. Fas Techs., Inc., 138 F.3d 1448, 1456 (Fed. Cir.
1998) (en banc). The ultimate determination of obvious-
ness is also a legal question this court reviews de novo,
but the jury’s underlying factual findings are reviewed for
substantial evidence. LNP Eng’g Plastics, Inc. v. Miller
Waste Mills, Inc., 275 F.3d 1347, 1353 (Fed. Cir. 2001).

    JMOL is appropriate on an issue when “a reasonable
jury would not have a legally sufficient evidentiary basis
to find for the party on that issue.” Fed. R. Civ. P.
50(a)(1). This court reviews a district court’s denial of
JMOL under the law of the regional circuit. Orion IP,
LLC v. Hyundai Motor Am., 605 F.3d 967, 973 (Fed. Cir.
2010). The Eleventh Circuit reviews all evidence in the
light most favorable to the nonmoving party and deter-
mines if there was any legally sufficient basis on which a
reasonable jury could find in favor of that party—the
same standard applied by the district court. Advanced
Bodycare Solutions LLC v. Thione Int’l, Inc., 615 F.3d
1352, 1360 (11th Cir. 2010).

B. Federal Rule of Civil Procedure 26 and 35 U.S.C. § 282

    DeAngelo’s principal argument is that the district
court erred by excluding the engineering drawings dis-
closed on February 8, 2010, as an untimely interrogatory
supplement despite DeAngelo’s identification of the
drawings immediately upon finding them and on the final
day of the scheduled discovery period. DeAngelo points
out that it stated in its initial interrogatory response that
it had not decided which prior art references it would use
and would disclose the references on which it would rely
as required by 35 U.S.C. § 282. It is undisputed that
these drawings were disclosed more than thirty days
before trial as specified by § 282. DeAngelo also argues
that the court failed to address its contention that MES
WOODS   v. DEANGELO MARINE                              9
waived its right to object to the drawings by not objecting
when it received them.

    MES counters that the court properly excluded the
drawings because DeAngelo failed to supplement its
answer to MES’s Interrogatory 25, failed to justify its late
disclosure, and failed to show that the late disclosure was
harmless.     Oral Arg. at 20:50-21:20, available at
http://www.cafc.uscourts.gov/oral-argument-recordings/
2010-1478/all/woods.html.       Accordingly, this appeal
requires us to determine whether the district court
abused its discretion by excluding the drawings, despite
DeAngelo’s discovery and disclosure of the drawings
within the thirty-day period required by § 282, and within
the discovery period set by the court.

                             1.

    We begin by disposing of DeAngelo’s argument that
MES waived its right to object to the drawings. DeAngelo
cites several cases to support its contention that MES
waived its right to object by not doing so when it received
DeAngelo’s letter disclosing the drawings and supple-
menting its interrogatory answer. See Butler v. Pettigrew,
409 F.2d 1205, 1207 (7th Cir. 1969) (finding waiver when
plaintiffs did not object until after entry of judgment);
Sure Fill & Seal, Inc. v. GFF, Inc., 2010 WL 3063287, at
*7 n.4 (M.D. Fla. July 6, 2010) (citing Brandt v. Vulcan,
Inc., 30 F.3d 752, 756-57 (7th Cir. 1994)). Those cases
merely support the proposition that a trial court’s decision
whether or not to find waiver is discretionary—they do
not compel this court to find that a district court abuses
its discretion when it does not find waiver in a case like
this. Here, the district court was given no clear basis on
which to find waiver, and we see no reason to question the
district court’s actions or re-visit the issue. Accordingly,
we turn to the merits of DeAngelo’s argument.
10                                WOODS v. DEANGELO MARINE

                             2.

    This court generally reviews application of the Fed-
eral Rules of Civil Procedure by applying the law of the
regional circuit. Trilogy Commc’ns, Inc. v. Times Fiber
Commc’ns, Inc., 109 F.3d 739, 744 (Fed. Cir. 1997). The
Eleventh Circuit has recognized that courts have broad
discretion to fashion discovery sanctions. United States v.
Certain Real Prop. Located at Route 1, Bryant Ala., 126
F.3d 1314, 1317 (11th Cir. 1997). Issues that are “unique
to patent law,” however, are reviewed as a matter of
Federal Circuit law. O2 Micro, 467 F.3d at 1364. The
application of § 282 is “unique to patent law.” Thus,
Federal Circuit law governs its application.

    Rule 26 imposes an obligation on parties to conduct a
reasonable inquiry into the factual basis of their discovery
responses and requires that a party who “responded to an
interrogatory . . . supplement or correct its disclosure or
response . . . in a timely manner if the party learns that in
some material respect the disclosure or response is in-
complete or incorrect . . . .” Fed. R. Civ. P. 26 (e)(1); see
also id. 26(b),. Indeed, the district court has discretion,
when circumstances warrant, to exclude evidence not
produced in compliance with a proper discovery request.
See Goodman-Gable-Gould, 595 F.3d at 1210-13 (affirm-
ing the district court’s exclusion of evidence because
statements made during a deposition and references to
relevant expenses in a discovery supplement did not
provide notice of the party’s theory of liability; those
disclosures did not constitute a supplement at all); see
also Innogenetics, N.V. v. Abbott Labs., 512 F.3d 1363,
1375-76 (Fed. Cir. 2008) (affirming the district court’s
exclusion of a prior art patent disclosed on the final day of
discovery because “the time for depositions had passed
[and] Abbott had not discussed the Cha patent in an
expert report, identified it during discovery in response to
WOODS   v. DEANGELO MARINE                              11
Innogenetics’ interrogatories on anticipation, or men-
tioned it in the final pretrial conference”).

    Contention interrogatories—like the interrogatory
here—serve an important purpose in helping to discover
facts supporting the theories of the parties. Answers to
contention interrogatories also serve to narrow and
sharpen the issues thereby confining discovery and sim-
plifying trial preparation. See Fed. R. Civ. P. 33 advisory
committee’s note (1970 Amendment, Subdivision (b)).
This court has recognized that answers to contention
interrogatories evolve over time as theories of liability
and defense begin to take shape; answers to those inter-
rogatories may not come into focus until the end of discov-
ery. See O2 Micro, 467 F.3d at 1365. Rule 26(e) requires
that as theories mature and as the relevance of various
items of evidence changes, responses to interrogatories,
and particularly contention interrogatories, be corrected
or supplemented to reflect those changes.

    The district court has considerable discretion in over-
seeing compliance with the Federal Rules of Civil Proce-
dure, including discretion to permit parties to defer
supplementing responses to contention interrogatories
until theories of the case have ripened for trial. Given
that deferred responses to contention interrogatories may
result in considerable last minute activity in preparation
for trial, however, some courts have passed local rules
limiting the extent to which parties are at liberty to defer
answering contention interrogatories. See id. at 1365-66.
Independent of the existence, vel non, of such local rules,
district courts have discretion to exclude evidence when a
party acts in bad faith or prejudices its adversary by
deliberately delaying, or wholly failing, to respond to
contention interrogatories. See Zenith Elecs. Corp. v. WH-
TV Broad. Corp., 395 F.3d 416, 420 (7th. Cir. 2005) (“The
district judge banned evidence on that subject after WH-
TV failed to respond to Zenith’s contentions interrogatory
12                                  WOODS v. DEANGELO MARINE

with a description of its damages theory and the proof to
be employed. . . . His decision was not an abuse of discre-
tion.”).

    Recognizing the evolving nature of the contentions of
the parties leading up to trial and to protect patentees
from unfair and prejudicial surprise at trial, Congress
established 35 U.S.C. § 282 to provide a statutory outer
limit for the disclosure of certain information relating
specifically to defenses to be relied upon by an accused
infringer at trial. Section 282 requires notice in writing:

     at least thirty days before the trial, of . . . any pub-
     lication to be relied upon . . . as showing the state
     of the art, and the name and address of any per-
     son who may be relied upon as the prior inventor
     or as having prior knowledge of or as having pre-
     viously used or offered for sale the invention of the
     patent in suit. In the absence of such notice proof
     of the said matters may not be made at the trial
     except on such terms as the court requires.

    Section 282 does not eliminate a defendant’s obliga-
tions under the Federal Rules of Civil Procedure. To the
contrary, the statute and the rules are intended to coexist.
See ATD Corp. v. Lydall, Inc., 159 F.3d 534, 551 (Fed. Cir.
1998) (“The purpose of § 282, like that of the Federal
Rules, is to prevent unfair and prejudicial surprise, not to
facilitate last-minute production of evidence.”); see also
Thermo King Corp. v. White’s Trucking Serv., Inc., 292
F.2d 668, 674 (5th Cir. 1961).

                               3.

    During the hearing on MES’s motion to exclude the
drawings, the district court treated the timing of the
production of the drawings and the supplementation of
the interrogatory as two separate, but related issues. See
Prior Art Argument at 3-8. When gathering the facts
WOODS   v. DEANGELO MARINE                               13
necessary to its decision, the district court inquired: “Why
were [the drawings] not produced in an earlier fashion
and why was the answer to the interrogatory not supple-
mented at an earlier time.” Id. at 8 (emphasis added).
After receiving DeAngelo’s response describing why the
documents were not produced earlier, the district court
again asked “why wasn’t the answer to the interrogatory
supplemented?” Id. at 12. In issuing its decision, the
district court specifically considered DeAngelo’s conten-
tion that the e-mail of February 8, 2010 was a supplement
to Interrogatory 25. Id. at 24. The court quoted the e-
mail, which was admittedly “general,” and concluded that
the e-mail was “not a timely supplement to the pro-
pounded interrogatory.” Id.

    While the ruling by the district court did not explicitly
address the propriety of the supplementation and focused
primarily on the issue of timeliness, the record is clear
that both issues were presented to the district court and
are reiterated before us on appeal. MES specifically
argues that “[w]hile DeAngelo provided the documents to
MES’s attorney on February 8, 2010, DeAngelo did not
clearly state the purpose of the documents or how they
might be used.” Appellee’s Br. 20. MES thus argues that
the February 8 e-mail “did not serve to supplement the
mandatory Rule 26 disclosures or the interrogatory re-
sponses.” Id. at 22 (emphasis added). Woods also specifi-
cally raised the issue at oral argument, stating “there was
no Rule 26(e) disclosure—the providing of the documents
without answering the questions that we actually asked
and without giving us the information that we actually
needed is not a satisfactory Rule 26(e) disclosure.” See
Oral Arg. at 20:48-21:04.        Thus, the “issue” here—
whether DeAngelo’s e-mail of February 8 constituted an
adequate and timely supplement to its interrogatory
response—includes consideration of both the timeliness of
the response and the propriety of the supplementation of
the interrogatory itself.
14                                 WOODS v. DEANGELO MARINE

                              4.

    The district court held that the documents in question
were not timely produced and imposed a sanction under
Rule 37(c) for their late production. To be sure, § 282, in
requiring that a party “give notice . . . in writing to the
adverse party at least thirty days before the trial, . . . of
any publication to be relied upon as anticipation of the
patent in suit or . . . as showing the state of the art,”
imposes only a minimum limit on the duty to disclose
prior art references. The district court, by local rule 1 or
by court order, 2 may require such production at an earlier
date. But the problem here is that there was no such
local rule or court order, save the order setting a discovery
deadline of February 9, 2010. The documents were dis-
closed on February 8, before the discovery deadline and
before the thirty day outer limit set by § 282. Further-
more, Rule 26(e) requires only that parties supplement
prior discovery responses “in a timely manner if the party
learns that in some material respect the disclosure or
response is incomplete or incorrect . . . .” Fed. R. Civ. P.
26(e)(1)(A) (emphasis added). The rule prohibits parties
who are aware of their deficient response from “hold[ing]
back material items and disclos[ing] them at the last
moment.” 8A Charles Alan Wright & Arthur R. Miller,
Federal Practice and Procedure § 2049.1 (3d ed. 2011); see
also Fed. R. Civ. P. 26 advisory committee’s note (1993

     1  See, e.g., N.D. Cal. Patent Local R. 3-3 to 3-4 (“Not
later than 45 days after service upon it of the ‘Disclosure
of Asserted Claims and Infringement Contentions,’ each
party opposing a claim of patent infringement, shall serve
on all parties its ‘Invalidity Contentions’ . . . [including a]
copy or sample of the prior art . . . .”).
    2   See Fed. R. Civ. P. 26(e) (“A party who has made a
disclosure . . . [or response to a discovery request] must
supplement or correct its disclosure or response . . . as
ordered by the court.”).
WOODS   v. DEANGELO MARINE                               15
Amendment, Subdivision (e)) (“The obligation to supple-
ment disclosures and discovery responses applies when-
ever a party learns that its prior disclosures or responses
are in some material respect incomplete or incorrect.”).
DeAngelo disclosed the drawings within one day of their
discovery and thus did not shirk its obligations under
Rule 26(e) with respect to timely production of the draw-
ings. Whether DeAngelo made a reasonable inquiry in
the first instance, however, as to the whereabouts of such
drawings is unclear. But we need not answer that ques-
tion as the issue before us can be resolved on the basis of
the inadequacy of the supplementation itself.

    This court agrees with the district court that Rule
26(e) was violated and concludes that the district court
imposed an appropriate sanction. The interrogatory in
question did more than require the identification of
documents (a requirement that DeAngelo satisfied by the
production). It requested that DeAngelo “[s]tate with
specificity all prior art that anticipates such claims of one
or more of the patents at issue or renders them obvious.
In doing so, specify the particular claim being referred to
and identify why such prior art anticipates such claims or
renders them obvious.” Mot. to Strike Drawings at 1-2
(emphasis added). While DeAngelo’s e-mail of February
8, 2010 (in which it disclosed the drawings) stated that
the drawings “may anticipate the Woods inventions, or
may be relied upon as showing the state of the art in the
early 1990’s,” DeAngelo did not comply with the empha-
sized requirements before the discovery deadline. Such
compliance was important. As discussed above, conten-
tion interrogatories serve an important purpose in ena-
bling a party to discover facts related to its opponent’s
contentions. In order for MES to have an opportunity to
meaningfully challenge DeAngelo’s reliance on the draw-
ings as prior art (including whether the drawings were
published or whether devices made from the drawings
contained the claimed features and were in fact on sale in
16                               WOODS v. DEANGELO MARINE

the early 1990s), it would have needed to know what
features of the drawings DeAngelo contended rendered
MES’s patents obvious on a claim-by-claim basis. 3 See
Innogenetics, 512 F.3d at 1376 (“Abbott’s disclosure of the
Cha patent as an anticipatory prior art reference on the
very last day of discovery meant Innogenetics was
stripped of any meaningful opportunity to prepare an
adequate cross-examination of the reference.”). Having
failed to provide MES with this information, DeAngelo’s
purported supplement of its response to Interrogatory 25
was in violation of Rule 26(e).

     Having properly found that DeAngelo’s failure to sup-
plement its interrogatory response was a violation of Rule
26(e), the district court was well within its discretion in
excluding the drawings under Federal Rule of Civil Pro-
cedure 37(c). The court found that DeAngelo’s failure to
supplement its interrogatory response harmed MES
because the drawings themselves were not prior art, and
MES would need to depose people and subpoena records
to defend against testimony that these drawings would
elicit. Prior Art Argument at 25-30. The court found that
MES could not cure this harm at such a late stage. Id.
This court sees no error in the district court’s explicit
findings that DeAngelo’s failure to supplement its inter-
rogatory response prejudiced MES and hindered MES’s
ability to put on its case and that this error was not
substantially justified or harmless. See Fed. R. Civ. P.
37(c) (“If a party fails to [supplement an interrogatory
response] as required by Rule [26(e)], the party is not
allowed to use that information . . . to supply evidence on
a motion, at a hearing, or at a trial, unless the failure was
substantially justified or is harmless.”); see also Eaton
Corp. v. Appliance Valves Corp., 790 F.2d 874, 879 (Fed.

     3  DeAngelo conceded at oral argument that the
drawings do not anticipate the MES patents. Oral Arg. at
4:35-4:55.
WOODS   v. DEANGELO MARINE                               17
Cir. 1986) (“The boundaries of the district court’s discre-
tion are defined by unfair, prejudicial harm to a party
deprived of an adequate opportunity to present its case.”).
Thus we find that the district court did not abuse its
discretion in precluding DeAngelo from relying on the
drawings as prior art.

                  C. Claim Construction

    DeAngelo next argues that the district court erred in
its construction of four disputed claim terms. According
to DeAngelo, the court’s constructions fail to account for
the inventions’ physical and functional limitations re-
quired by the specifications. See ICU Med., Inc. v. Alaris
Med. Sys., Inc., 558 F.3d 1368, 1375-76 (Fed. Cir. 2009).
MES counters that DeAngelo merely proposes alternative,
more restrictive descriptions of terms that already have a
clear meaning to one of skill in the art, and the district
court’s construction correctly refrains from reading un-
necessary limitations into the claims. See Phillips v.
AWH Corp., 415 F.3d 1303, 1323 (Fed. Cir. 2005) (en
banc).

    Claim terms are given their ordinary and customary
meaning—the meaning that they would have to a person
of ordinary skill in the art in light of the specification and
prosecution history at the time of the invention. Id. at
1312-13. The specification need not describe every em-
bodiment of the claimed invention, see Netword, LLC v.
Centraal Corp., 242 F.3d 1347, 1352 (Fed. Cir. 2001), and
the claims should not be confined to the disclosed em-
bodiments—even when the specification discloses only one
embodiment, Phillips, 415 F.3d at 1323.

    Claim terms are properly construed to include limita-
tions not otherwise inherent in the term only “when a
patentee sets out a definition and acts as his own lexicog-
rapher,” or “when the patentee disavows the full scope of
a claim term either in the specification or during prosecu-
18                               WOODS v. DEANGELO MARINE

tion.” Thorner v. Sony Computer Entm’t Am. LLC, 669
F.3d 1362, 1365 (Fed. Cir. 2012). “To act as its own
lexicographer, a patentee must ‘clearly set forth a defini-
tion of the disputed claim term’ . . . .” Id. (quoting CCS
Fitness, Inc. v. Brunswick Corp., 288 F.3d 1359, 1366
(Fed. Cir. 2002)). Moreover, “[w]here the specification
makes clear that the invention does not include a particu-
lar feature, that feature is deemed to be outside . . . the
patent, even though the language of the claims, read
without reference to the specification, might be considered
broad enough to encompass the feature in question.” Id.
at 1366 (internal citation omitted). As detailed below, the
district court’s construction of each term is consistent
with the plain meaning of the term, while DeAngelo’s
constructions require us to adopt limitations not defined
in, or required by, the specification.

                1. “elongated outer shell”

     DeAngelo argues that the court’s construction of the
claimed expression “elongated outer shell” as “the outer
pipe that extends past the spray ring,” is overly broad and
should be limited to outer shells having a length sufficient
to deflect and break apart water from the spray ring—the
function stated in the specification. MES counters that
the plain meaning of “elongated” outer shell is simply that
the outer shell extends past the spray ring. MES points
to claims that cover an embodiment where the water is
not directed toward the outer shell. See ’633 Patent col. 7
ll. 45-62; ’670 Patent col. 6 ll. 17-33. MES thus contends
that defining the term “elongated outer shell” as a shell
long enough to deflect water improperly reads a limitation
into the term—a limitation not required by every em-
bodiment.

    MES is correct. Nothing in the plain meaning of
“elongated outer shell” requires that the shell extend far
enough past the inner shell to serve as a deflection plane
for water. In fact, “elongated” is an adjective used to
WOODS   v. DEANGELO MARINE                             19
describe both the inner liner and outer shell within the
same claim. Compare ’633 Patent col. 7 l. 48 (“an elon-
gated inner liner”), with ’633 Patent col. 7 l. 50 (“an
elongated outer shell”). Therefore “elongated” cannot
mean long enough to provide a deflection surface; and
“outer shell” simply refers to the outer cylinder. Woods’s
abandonment of the ’097 Application, an event that
DeAngelo stresses in its obviousness argument, further
undermines DeAngelo’s claim construction argument.
The claims of the abandoned ’097 Application expressly
required a deflection surface for the sprayed water. The
’670 Patent’s claims do not have such a limitation.

    The patentee did not expressly define “elongated outer
shell” as providing a deflection surface, nor did he dis-
avow an outer liner that does not deflect water. This
court will not read such a limitation into the term merely
because it is disclosed in some embodiments. Phillips,
415 F.3d at 1323. The district court correctly construed
“elongated outer shell.”

              2. “inwardly tapered section”

    DeAngelo next argues that the court erred in constru-
ing the phrase “inwardly tapered section” as “the section
of the elongated outer shell or elongated inner liner that
has a reduction in diameter.” Just as DeAngelo urged us
to limit “elongated outer shell” to account for the “func-
tional limitation” of a water deflection surface, it argues
that “inwardly tapered section” should also be so limited.
According to DeAngelo, the term should be construed to
require the tapered section occur near the tail end of the
shell, so water can deflect off of the tapered surface. In
support, DeAngelo points to embodiments in the specifica-
tion where water collides with the inwardly tapered
section. See, e.g., ’670 Patent col. 2 ll. 25-28. MES dis-
agrees and argues that while some embodiments may
indeed function by deflecting water off of the tapered
surface into the exhaust stream, the claims need not be
20                               WOODS v. DEANGELO MARINE

restricted to that embodiment. We see nothing in the
claims or written description to warrant limiting this
term to a single embodiment. The district court correctly
construed “inwardly tapered section” not to require a
deflection surface.

                   3. “directed towards”

    DeAngelo argues that the district court’s construction
of the phrase “directed towards” as “caused to flow in a
direction that results in contact with,” is overly broad
because the specification requires the water to hit the
liner with enough force to fan out, not merely contact the
liner. MES counters that the ordinary meaning of the
phrase “directed towards” is clear and unencumbered
with the additional limitation DeAngelo seeks to incorpo-
rate. According to MES, nothing warrants adding the
requirement of a forceful collision to the term “directed
towards.”

     The district court’s construction of “directed towards”
is correct. Like the other disputed terms, the specification
does not require the water to forcefully collide with a
surface. For example, some claims specifically require
that the water forcefully exit the spray ring and flow
towards a wall, other claims do not require such force.
Compare ’670 Patent col. 6 l. 64-col. 7 l. 4, with ’633
Patent col. 8 ll. 49-53. The patentee never expressly
defined “directed towards,” nor did he disavow the clear
definition found by the district court. This court will not
construe this otherwise clear term to include a limitation
already present in some claims but not others.

                 4. “angularly disposed”

    Finally, DeAngelo argues that the district court’s con-
struction of “angularly disposed” as “a spray ring posi-
tioned in a way that is not parallel or perpendicular to the
central axis of the inner liner” is overbroad because it
WOODS   v. DEANGELO MARINE                                  21
does not limit the spray of the water stream towards the
outer shell. DeAngelo claims that the court’s construction
allows a spray ring that directs water towards the inner
liner, an embodiment not described in the specification.
Acording to DeAngelo, “[t]he specifications of each of the
Patents-in-Suit disclose only two possible orientations for
the spray ring,” at an approximately 90° angle relevant to
the central axis, or directed towards the outer liner.
Appellant’s Br. 55. MES accuses DeAngelo of again
reading an unwarranted limitation into the claims based
on specific embodiments, in contravention of Phillips. 415
F.3d at 1323.

    The district court’s construction comports with the or-
dinary meaning of this term. The phrase “angularly
disposed” does not prescribe any specific angle. The
patentee never defined the term nor disavowed a broader
meaning. Furthermore, it is not necessary to read DeAn-
gelo’s proposed limitation into the term because every
claim that uses this term already limits the ring to being
directed toward the outer wall. See ’670 Patent col. 6 l.
54-col. 7 l. 4, col. 7 l. 12-col. 8 l. 12; ’633 Patent col. 8 ll.
35-53, col. 9 ll. 11-18.

    The district court correctly declined to read unwar-
ranted limitations into the disputed claim terms. For the
foregoing reasons, this court affirms the district court’s
claim construction.

                          D. Validity

    DeAngelo challenges the district court’s denial of
JMOL that the asserted claims of Woods’s patents are
invalid as obvious under 35 U.S.C. § 103. DeAngelo sets
forth three main arguments in support of its obviousness
contention. First, DeAngelo argues that the prior art
patents contain every limitation of Woods’s asserted
claims, and Woods admitted as much during prosecution
when he chose to add an additional claim limitation
22                               WOODS v. DEANGELO MARINE

instead of arguing to the examiner that the reference did
not anticipate the claim. DeAngelo then argues that its
excluded prior art drawings, see supra § II.B., render the
claims obvious. Finally, DeAngelo contends that the Key
Marine Riser, a product that predates Woods’s patents,
exhibits a tapered inner liner, the only element of the
asserted claims that is arguably not shown in the prior
art patents.

     MES counters that the prior art references do not
show every limitation of Woods’s asserted claims; they
specifically lack any teaching of a tapered inner liner.
MES also argues that because DeAngelo’s prior art draw-
ings were properly excluded, they cannot support an
obvious rejection. Moreover, MES argues that the jury
had the opportunity to observe the Key Marine Riser and
still concluded that it did not render the claims of Woods’s
patents obvious. Finally, MES characterizes Woods’s
patents as having solved a longstanding problem in the
marine exhaust industry and that such a showing is
objective evidence of non-obviousness.

    The Supreme Court reaffirmed the appropriate obvi-
ousness analysis in KSR International Co. v. Teleflex Inc.,
550 U.S. 398 (2007). The Court instructed us to: (1)
determine the scope and content of the prior art, (2)
ascertain the differences between the prior art and the
claims at issue, (3) resolve the level of ordinary skill in
the art, and (4) determine obviousness in light of objective
factors like “commercial success, long felt but unsolved
needs, failure of others, etc.” KSR, 550 U.S. at 406 (quot-
ing Graham v. John Deere Co. of Kansas City, 383 U.S. 1,
17-18 (1966)). At bottom, the obviousness analysis is a
common sense test, and “[i]f a person of ordinary skill . . .
would have found the invention [a] predictable and
achievable variation or combination of the prior art, then
the invention likely would have been obvious.” Rolls-
WOODS   v. DEANGELO MARINE                            23
Royce, PLC v. United Techs. Corp., 603 F.3d 1325, 1338
(Fed. Cir. 2010) (citing KSR, 550 U.S. at 417, 421).

                1. The Prior Art Patents

    DeAngelo first contends that because all claims of
Woods’s initial ’097 Application were rejected as antici-
pated by the Shiozawa and Moffit references, Woods’s
abandonment of the ’097 Application is “an inference, if
not an admission that the claims of that application are
unpatentable as being anticipated by both Shiozawa and
Moffit (thus defining the scope and content of the prior
art).” Appellant’s Br. 36. MES contests that assertion
and cites Paperless Accounting v. Bay Area Rapid Transit
System, 804 F.2d 659 (Fed. Cir. 1986), to support the
proposition that Woods’s decision to abandon the ’097
Application and pursue the broader ’548 Application
cannot constitute even an inference that the ’097 Applica-
tion was properly rejected. MES argues that although
Shiozawa and Moffit are within the prior art, neither
teaches an inwardly tapered tail end of the inner liner.

    DeAngelo’s characterization of Woods’s abandonment
of the ’097 Application as an admission that the Shiozawa
and Moffit references disclose every element of Woods’s
patents is meritless. DeAngelo fails to consider that
Woods filed the ’548 Application more than six months
before the examiner rejected the ’097 Application. More-
over, the claims in the ’548 Application are arguably
broader than the claims in the ’097 Application, and
Woods prosecuted the ’548 Application before the same
examiner who eventually rejected the ’097 Application.
There is nothing to suggest that Woods did anything
other than simply choose to pursue the similar, but
broader, ’548 Application instead of continuing to prose-
cute the ’097 Application. This court declines to charac-
terize Woods’s conduct as an admission or concession that
the claims in the ’097 Application are anticipated by
Shiozawa or Moffitt.
24                              WOODS v. DEANGELO MARINE

    DeAngelo next contends that Woods’s amendment in
response to the examiner’s April 1, 1999 rejection consti-
tuted an admission that the originally filed claims of the
’821 Application (ultimately the ’633 Patent) were antici-
pated by Lulloff. DeAngelo argues that Woods acquiesced
to the substance of the examiner’s rejection because
Woods added a different limitation instead of arguing that
Lulloff does not teach a tapered liner. According to
DeAngelo, this qualifies as an admission that all limita-
tions in the initial claims, including the tapered liner,
existed in the prior art. DeAngelo urges us to preclude
MES from now arguing that Lulloff does not contain a
tapered liner.

    In TorPharm, Inc. v. Ranbaxy Pharmaceuticals, Inc.,
336 F.3d 1322, 1330 (Fed. Cir. 2003), this court rejected
Ranbaxy’s similar acquiescence rationale, explaining that
“Ranbaxy’s argument blurs the distinction between
claims and limitations: patentability is assessed for the
former, not the latter.” Explicit limitations are material
to the infringement inquiry. Id. at 1331 n.9. But viewing
an amendment as an admission that the initial claim was
unpatentable requires more than the mere presence of a
limitation. See id. at 1330.

    DeAngelo relies on a number of reissue proceeding
cases like Hester Industries, Inc. v. Stein, Inc., 142 F.3d
1472 (Fed. Cir. 1998), which address the surrender of
subject matter during the initial prosecution. But Hester
cites Mentor Corp. v. Coloplast, Inc., 998 F.2d 992, 995
(Fed. Cir. 1993), which suggests there must be additional
evidence (e.g., argument to the examiner) to support a
conclusion that an amendment was an admission. Hester,
142 F.3d at 1480-81. DeAngelo also relies on Lemelson v.
General Mills, Inc., 968 F.2d 1202, 1207-08 (Fed. Cir.
1992), to support its acquiescence theory. But in Lemel-
son, it is not clear to what extent the patentee argued the
rejection with the examiner. Id. Moreover, this court
WOODS   v. DEANGELO MARINE                              25
specifically distinguished Lemelson in TorPharm based on
similar facts to those here. TorPharm, 336 F.3d at 1331
n.9.

    This court does not accept DeAngelo’s acquiescence
theory as support for its contention that Lulloff contains a
tapered surface as a matter of law. The examiner rejected
the ’821 Application as anticipated by Lulloff, which
showed an elongated liner and shell with an inwardly
tapered section. Woods made no statement representing
that a tapered liner was not disclosed by Lulloff. He
never admitted it. He never addressed it. All he argued
to the examiner was that using a spacer to create back
pressure in the inner volume was not disclosed by Lulloff.
A patent applicant is not presumed to have conceded the
presence in the prior art of every claim limitation he had
no reason to dispute. This court has considered DeAn-
gelo’s other arguments that Woods’s specifications and
the prior art patents render the asserted claims of the
Woods patents obvious and finds them to be without
merit.

    2. Excluded Drawings and the Key Marine Riser

     DeAngelo also argues that its excluded drawings de-
monstrate that every limitation of the asserted claims
was known in the prior art. As discussed above, see supra
§ II.B, the district court properly excluded these drawings
and the drawings are properly excluded from the obvious-
ness analysis. Finally, DeAngelo relies on the “Key
Marine Riser,” a device presented to the jury, to show that
a tapered tail end existed in the prior art. But the jury
physically inspected the Key Marine Riser and was free to
conclude that it did not support DeAngelo’s theory.
DeAngelo has failed to show that the prior art singly or
collectively disclosed or taught every limitation of the
claims at issue. On this evidence, this court cannot say
that the jury could not have sustained the validity of the
claims at issue.
26                              WOODS v. DEANGELO MARINE

                  E. Non-Infringement

    DeAngelo’s argument that the district court erred in
denying its motion for JMOL of non-infringement is
relatively narrow. DeAngelo argues that MES failed to
introduce any infringement evidence, other than engi-
neering drawings, for DeAngelo’s “notched diffusers,” and
that no reasonable jury could have found infringement
based on those drawings. Although all of DeAngelo’s
products contain a hose bead, DeAngelo stresses that
Darrin Woods’s (MES’s vice-president) testimony explain-
ing how the hose bead creates a tapered surface dealt only
with “conical diffusers.” DeAngelo thus contends that, as
a matter of law, the “notched diffusers” cannot infringe.

    MES counters that at trial the jury heard testimony
that adding a “hose bead” to the end of a liner, regardless
of the type of diffuser, would cause an indentation and
tapering effect. Also, the jury was able to physically
inspect the Key Marine Riser and observe the taper that a
hose bead caused. MES argues that, in light of DeAn-
gelo’s admission that all of its products contain a hose
bead, the evidence of a hose bead induced taper was
sufficient for a reasonable jury to conclude that DeAn-
gelo’s notched diffusers also had a tapered liner and
infringed the Woods patents.

    MES is correct. DeAngelo admitted that all of its
products contain a hose bead. Darrin Woods testified that
a hose bead on the diffuser causes an indentation in the
liner resulting in the requisite tapered surface. Darrin
Woods’s testimony was a legally sufficient basis on which
the jury could have found that DeAngelo’s notched diffus-
ers infringed the asserted claims of the Woods patents.
The district court did not err by denying JMOL of non-
infringement.
WOODS   v. DEANGELO MARINE                             27
                  F. Rule 11 Sanctions

     Finally, DeAngelo alleges that MES and Woods filed
this lawsuit without conducting an adequate pre-suit
investigation into whether or not DeAngelo’s products
actually infringe. DeAngelo argues that MES decided to
file this lawsuit based only on photographs taken by an
MES employee and that MES’s attorney did not make an
adequate infringement determination prior to filing.
DeAngelo stresses that Woods made the decision to file
the infringement suit based only on grainy photographs
that Woods himself admitted did not clearly show the
elements of the claims. MES counters that the grainy
black and white photographs DeAngelo used to elicit
Woods’s testimony were not the same photos on which the
suit was based; the suit was based on the same high
definition color photos presented at trial and used to
prove infringement to the jury. Moreover, Woods and
MES point out that for over two years, DeAngelo denied
them the access to DeAngelo’s products that they sought
and that DeAngelo now argues was required.

    The Eleventh Circuit imposes Rule 11 sanctions
where the “frivolous nature of the claims-at-issue is
unequivocal.” Carter v. ALK Holdings, Inc., 605 F.3d
1319, 1323 (Fed. Cir. 2010). In a patent case, this court
stated that “an attorney violates Rule 11(b)(3) when an
objectively reasonable attorney would not believe, based
on some actual evidence uncovered during the prefiling
investigation, that each claim limitation reads on the
accused device . . . .” Antonious v. Spalding & Evenflo
Cos., 275 F.3d 1066, 1074 (Fed. Cir. 2002).

    Here, the record is replete with evidence supporting
the district court’s conclusion that MES conducted a
sufficient pre-filing investigation including photographing
and studying photographs of DeAngelo’s accused prod-
ucts. See supra § I.B. Nonetheless, DeAngelo argues that
Judin v. United States, 110 F.3d 780 (Fed. Cir. 1997),
28                               WOODS v. DEANGELO MARINE

compels the conclusion that MES’s mere observations of
DeAngelo products cannot constitute an adequate investi-
gation. DeAngelo’s reliance on Judin is misplaced. In
Judin, the plaintiff observed allegedly infringing products
from a distance, but never sought access to investigate
them more closely. Id. at 784. Here, MES directly re-
quested from DeAngelo, in writing, information about
DeAngelo’s allegedly infringing devices.        When that
information was not forthcoming, MES took the photo-
graphs of DeAngelo’s products that were used as the basis
for filing suit. At trial a number of witnesses testified
that they could discern the features covered by the as-
serted claims from the digital color photographs. This is
not a case like Judin where the plaintiff sued without
seeking access to examine allegedly infringing devices.
The district court did not abuse its discretion in declining
to sanction MES.

                       CONCLUSION

    For the foregoing reasons, the judgment of the district
court is affirmed.

                       AFFIRMED
