Well Master Corporation v. Flowco Production Solutions, LLC

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF COLORADO
Civil Action No. 21-cv-02145-CMA-KAS
WELL MASTER CORPORATION, a Colorado corporation,
Plaintiff and Counter Defendant,
v.
FLOWCO PRODUCTION SOLUTIONS, LLC, a Texas limited liability company,
Defendant and Counter Claimant.
_____________________________________________________________________
RECOMMENDATION OF UNITED STATES MAGISTRATE JUDGE
_____________________________________________________________________
ENTERED BY MAGISTRATE JUDGE KATHRYN A. STARNELLA
This matter is before the Court on Defendant/Counter Claimant Flowco Production
Solutions, LLC’s (“Flowco”) Motion to Exclude [#256] (the “Motion”). Plaintiff/Counter
Defendant Well Master Corporation (“Well Master”) filed a Response [#260] in opposition
to the Motion [#256] and Flowco filed a Reply [#263]. The Motion [#256] has been referred
to the undersigned. See Memorandum [#258]. The Court has reviewed the briefs, the
case file, and the applicable law. For the following reasons, the Court RECOMMENDS1
that the Motion [#256] be GRANTED.
I. Relevant Procedural History
On August 9, 2021, Well Master filed suit against Flowco, alleging infringement of
three patents for plungers used in oil and gas lift systems: U.S. Patent No. 7,395,865 (the
1 Although a Motion to Exclude [#256] is not plainly dispositive in nature, in an abundance of
caution, this Court will proceed by Recommendation given the potentially dispositive effect of
excluding evidence of an earlier priority date. Cf., e.g., Moss v. Home Depot U.S.A., Inc., No. 18-
cv-02760-REB-NYW, 2019 WL 5095719, at *1 (D. Colo. July 31, 2019) (magistrate judge deciding
two Rule 37 motions to strike experts on Recommendation because of their potentially dispositive
effect).
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‘865 patent), U.S. Patent No. 7,793,728 (the ‘728 patent), and U.S. Patent No. 8,627,892
(the ‘892 patent). Compl. [#1], ¶ 1. On October 8, 2021, Well Master filed an Amended
Complaint [#20], which Flowco moved to dismiss in part, particularly the claims of willful
infringement and claims relating to the ’865 patent. See Motion to Dismiss [#21] at 2.
Flowco did not initially file an answer.
On February 21, 2022, Flowco served its first set of discovery requests on Well
Master. See Def.’s First Set of Discovery to Pl. [#260-2]. Two of these requests,
Interrogatory 1 and Request for Production (“RFP”) 10, are relevant to the Motion [#256].
In full, Interrogatory 1 reads:
Describe with particularity the circumstances surrounding the invention and
patenting of the inventions claimed in the Patents-in-Suit, including the
precise date of conception, the Persons involved and nature of their
involvement, the dates of actual and constructive reduction to practice, the
steps constituting diligence from 	conception to actual or constructive
reduction to practice, drafting and submission of invention disclosures or
laboratory 	notebooks, 	patent 	application 	drafting, 	identification 	of 	all
Persons involved in the conception and/or reduction to practice, including a
description of his or her involvement, and all Documents that You contend
corroborate any of the foregoing.
Id. at 6. In full, RFP 10 seeks production of:
Documents sufficient to show the first written disclosure, first disclosure to
another, first public sale or offer for sale, effective priority date, and first
public use and/or public disclosure of each alleged invention described or
claimed in the Patents-in-Suit.
Id. at 11.
On March 15, 2022, Well Master supplemented its Initial Infringement Contentions
and represented that “no documents are believed to exist in Well Master’s possession,
custody, or control” responsive to D.C.COLO.LPtR 5(a) or 5(b). See Well Master’s First
Supp. Infringement Contentions [#46] at 6.
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On March 28, 2022, Well Master responded to written discovery but objected to
Interrogatory 1 and RFP 10, asserting in part that they were not relevant because Flowco
had not asserted the invalidity of the patents in suit. See Movant’s Appx. [#256-1] at 1-3,
[#263-1] at 26-30.2 Standing on its objections, Well Master did not substantively respond
to either Interrogatory 1 or RFP 10. Movant’s Appx. [#256-1] at 1-4, [#263-1] at 27-30.
On May 24, 2022, Magistrate Judge Kristen Mix issued an Order [#70] that
resolved multiple discovery motions, stating in part that “[p]ermitting discovery on a
defense such as invalidity is particularly appropriate in a case such as here where both
parties agreed to this procedure and it comports with the Local Patent Rules.” See Order
[#70] at 7. She noted that, even though Flowco had not yet answered, “discovery
regarding invalidity was permitted with leave of court. In fact, such discovery was agreed,
undertaken and ordered for at least five months before Plaintiff filed its Motion to Strike
[Defendant’s Initial Invalidity Contentions].” Id. at 3. She rejected Well Master’s reliance
on “unpublished cases outside of the Tenth Circuit to contend that ‘[Flowco] is not entitled
to take discovery on unpled claims or defenses[.]’” Id. at 6. Finally, she noted that in
January 2022 conferral emails, Well Master’s counsel had “contended that many of [Well
Master’s] document requests sought relevant information because they were directed to
‘identifying prior potential art.’” Id. at 4. She denied Well Master’s motion to strike Flowco’s
invalidity contentions and its related request for “a protective order precluding Defendant
from 	taking 	discovery 	on 	any 	unpled 	claims 	or 	defenses, 	including 	the 	invalidity
2 Flowco’s “Movant’s Appendix” is split between two docket entries: the first 25 pages are found
at [#256-1], attached to its Motion [#256], while pages 26-32 are found at [#263-1], attached to its
Reply [#263]. The documents include nonconsecutive portions of Well Master’s written discovery
responses and supplements, so in this Recommendation the Court will indicate the docket
number and cite to the “Movant’s Appendix p. #” indicated on the bottom of each page.
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contentions.” Id. at 2, 8.
On July 8, 2022, Well Master supplemented some of its discovery responses,
including RFP 10 (but not Interrogatory 1). See Movant’s Appx. [#263-1] at 29. As to RFP
10, Well Master stated that:
In view of the Court’s Order [ECF 70], Well Master renews its objection to
the request for production to the extent it seeks information which is not
relevant to the subject matter of the present lawsuit and is not reasonably
calculated to lead to the discovery of admissible evidence. Defendant has
not asserted in the Scheduling Order or in its Initial Invalidity Contentions
that any of the patents-in-suit are invalid based upon any written disclosure,
disclosure to another, public sale or offer for sale, or public use and/or public
disclosure. Therefore, Defendant is not currently entitled, under Fed. R. Civ.
P. 26(b)(1), to take discovery regarding these topics.
Well Master also further objects to this request for production to the extent
that it seeks production of documentation that is already in Defendant’s
possession and/or that is publicly-available [sic] to Defendant. Namely,
documents showing the effective priority date of the patents-in-suit
are available from the USPTO website.
Id. (emphasis added).
On August 9, 2022, Flowco filed petitions for inter partes review with the United
States Patent Trial and Appeal Board (“PTAB”), challenging the validity of the patents in
suit. See Motion to Stay [#83] at 1-2. Two weeks later, it moved to stay this case, which
the Court granted on September 12, 2022. Id.; Order [#98] at 17 (granting stay pending
inter partes review). The PTAB denied Flowco’s petitions for inter partes review and on
June 7, 2023, the Court lifted the stay and set claim construction briefing deadlines, with
briefing to conclude by August 31, 2023. See Order [#124] at 6. On June 30, 2023, Flowco
simultaneously filed a Partial Motion to Dismiss [#125] and an Answer and Counterclaim
[#126]. On September 7, 2023, Well Master served second supplemental discovery
responses, this time supplementing Interrogatory 1 with the following:
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Subject to the foregoing objections, pursuant to Fed. R. Civ. P. 33(d), Well
Master refers Defendant to the November 10, 2022 Declaration of David
Green and the exhibits thereto which was submitted to the United States
Patent Office Patent Trial and Appeal Board in IPR 2022-01384 and IPR
2022-01385.
Movant’s Appx. [#256-1] at 9-10.
On May 9, 2024, Well Master served a third supplement to its discovery responses,
this time responding to Interrogatory 1 with a detailed, three-and-a-half-page statement.
See id. at 18-21. In part, Well Master stated (relative to the ‘865 and ‘729 patents) that
Robert Bender had conceived of the design of Well Master’s Sand Viper plunger around
September 2003. Id. at 18. On October 18, 2003, Mr. Bender and David Green held a
strategic planning session in which Mr. Bender “drew a sketch for Mr. Green showing the
features of his new plunger design” and “described the functionality and theory” behind
the design. Id. Well Master disclosed a copy of the meeting agenda with Mr. Green’s
handwritten notes. Id. Commercial introduction was planned for the first quarter of 2004
but was delayed, and in mid-October 2004, Mr. Bender hired Mr. Green as a Well Master
employee. Id. at 19. At that time, Mr. Bender had prototypes made by Well Master’s
machine shop—these were “the first physical embodiments of Mr. Bender’s new plunger
design.” Id. Thus, “as of at least as early as October 2004, Mr. Bender had conceived of
and reduced his new plunger design to practice with Mr. Green’s assistance.” Id.
However, the commercial name for the design was not adopted until January 2005, when
the first technical drawing was created. Id. at 19-20. Well Master states that it filed U.S.
Provisional App. No. 60/593,914 on February 24, 2005, and that this provisional
application constitutes “constructive reduction to practice of the asserted claims of the
‘865 and ‘729 Patents.” Id. at 20. The application for the ‘865 patent was filed on February
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8, 2006, and the application for the ‘729 patent was “a continuation” of the application for
the ‘865 patent “and also claims priority to U.S. Provisional App. No. 60/593,914.” Id.
Finally, regarding the ‘892 patent, Well Master asserted that Rick Nadkrynechny
conceived of the design of Well Master’s Venturi plunger around October 1, 2007, “as
evidenced by his submission to the Canadian Scientific Research and Experimental
Development Tax Incentive Program[.]” Id. The first physical prototypes were created for
well testing in December 2009, and Well Master disclosed photographs. Id. at 20-21.
Thus, Well Master stated, “at least as early as December 2009, Mr. Nadkrynechny had
conceived of and reduced his new plunger design to practice.” Id. at 20-21.
On August 29, 2024, the Court entered its Order on Claim Construction [#262],
which triggered several other Scheduling Order deadlines. See Minute Order [#234].
Now, Flowco moves to preclude Well Master from relying on a priority date earlier than
the patents-in-suit’s filing dates, on the basis that Well Master failed to make disclosures
required under D.C.COLO.LPtR 5 and failed to timely supplement or correct its discovery
responses under Fed. R. Civ. P. 26(e). See Motion [#256] at 3.
II. Legal Standards
A. 	Local Patent Rule 5
In relevant part, D.C.COLO.LPtR 5 provides that
Contemporaneously with service of the Infringement Contentions, the party
claiming patent infringement shall produce to each party . . . the following
documents and identify by production number which documents correspond
to each category:
(a) 	All documents demonstrating each disclosure, sale (or offer to sell),
or any public use of the claimed invention before the application date
or the priority date (whichever is earlier) for each patent in suit;
(b) 	All documents created on or before the application date or the priority
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date (whichever is earlier) for each patent in suit that demonstrate
each 	claimed 	invention’s 	conception 	and 	earliest 	reduction 	to
practice;
[. . .]
Unfortunately, “[t]here is a dearth of case law in the District of Colorado regarding
D.C.COLO.LPtR 5; in fact, the Court has found no written opinions citing this Local Rule.”
Seeley Int’l Pty Ltd v. Maisotsenko, No. 21-cv-01350-CMA-KLM, 2022 WL 3975005, *6
(D. Colo. Sept. 1, 2022). Based on the Court’s research, this remains true two years
later—Seeley is the only case the Court could find that discusses Local Patent Rule 5.
As the Federal Circuit has noted, local patent rules are “designed specifically to
‘require parties to crystallize their theories of the case early in the litigation’ so as to
‘prevent the “shifting sands” approach to claim construction.’” O2 Micro Int’l Ltd. v.
Monolithic Power Sys., Inc., 467 F.3d 1355, 1364 (Fed. Cir. 2006) (quoting Atmel Corp.
v. Info. Storage Devices, Inc., No. C 95-1987 FMS, 1998 WL 775115, at *2 (N.D. Cal.
Nov. 5, 1998)). In many cases, the party claiming infringement has in its possession
evidence of priority even before it files suit—so “[e]ven when discovery reveals an
unforeseen earlier priority date, there is rarely a justifiable excuse for shifting a priority
date contention near the end of fact discovery.” Elbit Sys. Land & C4I Ltd. v. Hughes
Network Sys., LLC, No. 2:15-cv-00037-RWS-RSP, 2017 WL 2651618, at *10 (E.D. Tex.
June 20, 2017) (discussing Eastern District of Texas Local Rule 3-1(e)); see also
Thought, Inc. v. Oracle Corp., No. 12-cv-05601-WHO, 2015 WL 5834064, at *5 (N.D. Cal.
Oct. 7, 2015) (“The purpose of the local rules to crystallize the parties’ theories early in
litigation would be frustrated if [N.D. Cal.] Patent Local Rule 3-1 and 3-2 were read to
allow a plaintiff to avoid specifying a conception date or provide any documents that
support this date.”). Thus, while the spirit of the Local Patent Rules is clear, the lack of
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case law applying or construing D.C.COLO.LPtR 5 leaves the Court with little guidance.3
B. 	Fed. R. Civ. P. 26(e) and 37(c)
Discovery in patent cases, like all other civil cases, is governed by the Federal
Rules of Civil Procedure. Cf. Teashot LLC v. Green Mountain Coffee Roasters, Inc., No.
12-cv-00189-WJM-KMT, 2014 WL 485876, at *6 (D. Colo. Feb. 6, 2014).
Rule 26(e)(1)(A) imposes an ongoing duty on parties to supplement or correct their
disclosures and discovery responses “in a timely manner if the party learns that in some
material respect the disclosure or response is incomplete or incorrect, and if the additional
or corrective information has not otherwise been made known to the other parties during
the discovery process or in writing[.]” Rule 37(c)(1) imposes penalties for parties who
violate Rule 26(e): “If a party fails to provide information . . . 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.” Courts
have used Rule 37(c)(1) to exclude certain theories of infringement in patent cases,
“because each new theory necessarily requires new evidence or witnesses.” Teashot,
2014 WL 485876, at *8 (citing Tritek Techs., Inc. v. United States, 63 Fed. Cl. 740, 749
3 Moreover, other jurisdictions’ local patent rules do not mirror D.C.COLO.LPtR 5 in either
numbering or content. See, e.g., N.D. Cal. Pat. R. 3-1(f) (requiring an early disclosure that
includes “[f]or any patent that claims priority to an earlier application, the priority date to which
each asserted claim allegedly is entitled[.]”); N.D. Cal. Pat. R. 3-2(b) (requiring document
production accompanying this disclosure to include “[a]ll documents evidencing the conception,
reduction to practice, design, and development of each claimed invention, which were created on
or before the date of application for the patent in suit or the priority date identified pursuant to
Patent L.R. 3-1(f), whichever is earlier[.]”); E.D. Tex. Pat. R. 3-1(e) (requiring a similar disclosure
including, “[f]or any patent that claims priority to an earlier application, the priority date to which
each asserted claim allegedly is entitled”). By contrast, Colorado’s analogous Local Patent Rule
5 does not explicitly require identification of a priority date and only requires production of
documents “that demonstrate each claimed invention’s conception and earliest reduction to
practice[.]” D.C.COLO.LPtR 5(b).
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(Fed. Cl. 2005); Transclean Corp. v. Bridgewood Servs., Inc., 290 F.3d 1364, 1374 (Fed.
Cir. 2002)).
Rule 26(e) prohibits parties who are aware that their responses are deficient “from
holding back material items and disclosing them at the last moment.” Teashot, 2014 WL
485876, at *7 (internal quotation marks and modifications omitted) (quoting Woods v.
DeAngelo Marine Exhaust, Inc., 692 F.3d 1272, 1282 (Fed. Cir. 2012)). Thus, the
question of timeliness focuses on the disclosing party’s explanation for the late disclosure,
and particularly on when it learned the late-disclosed information. See, e.g., Integra
LifeSciences Corp. v. Hyperbranch Med. Tech., Inc., No. 15-819-LPS-CJB, 2018 WL
3814614, at *3 (D. Del. Mar. 23, 2018) (striking the plaintiffs’ “belated shift in the asserted
priority date” as untimely due to prejudice and a lack of adequate explanation); Elbit Sys.
Land & C4I Ltd., 2017 WL 2651618, at *10 (finding that the plaintiff’s January 2017
supplement to its interrogatory response was untimely under Rule 26(e)(1) where “it is
undisputed that [the plaintiff] possessed the underlying facts at least by September
2016”). That the other side did not complain to the court does not excuse untimeliness
because “[a] party has the right to assume that opposing counsel is acting with diligence,
and in compliance with the Federal Rules of Civil Procedure, during discovery.” Teashot,
2014 WL 485876, at *7.
Finally, where a court finds a violation of Rule 26(e), determining whether the late
disclosure is substantially justified or harmless under Rule 37(c) is within the district
court’s broad discretion. Woodworker’s Supply, Inc. v. Principal Mut. Life Ins. Co., 170
F.3d 985, 993 (10th Cir. 1999); see also Eaton Corp. v. Appliance Valves Corp., 790 F.2d
874, 879 (Fed. Cir. 1986) (“The boundaries of the district court’s discretion are defined by
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unfair, prejudicial harm to a party deprived of an adequate opportunity to present its
case.”) (citations omitted). The Tenth Circuit has instructed district courts to consider four
factors: (1) the prejudice or surprise to the party against whom the evidence is offered;
(2) the ability to cure the prejudice; (3) the extent to which introducing such evidence
would disrupt the proceeding; and (4) the moving party’s bad faith or willfulness.
Woodworker’s Supply, 170 F.3d at 993; Integra LifeSciences, 2018 WL 3814614, at *1
(applying the Third Circuit’s equivalent to the Woodworker’s Supply factors in a patent
case).
III. Analysis
Flowco argues that Well Master did not comply with D.C.COLO.LPtR 5 because in
its infringement contentions, it expressly represented that it had no documents responsive
to Local Patent Rule 5(a) or 5(b), indicating priority dates no earlier than each patent-in-
suit’s application date. Motion [#256] at 7. Additionally, Flowco argues that Well Master
did not timely supplement its disclosures or its discovery responses pursuant to Fed. R.
Civ. P. 26(e), because the information and documents referenced in Well Master’s third
supplemental response to Interrogatory 1 are “Well Master’s own documents and
information from its own internal records” which it has long possessed. Id. at 6-8. Flowco
argues that the untimely disclosure prejudiced it in searching for prior art. Id. at 10.
Well Master does not argue that it recently obtained this information or that it acted
diligently to produce it. See generally Response [#260]. Instead, it argues that Flowco
has not shown a violation of Local Patent Rule 5(a) or 5(b) because it has not identified
which produced documents supposedly fall into each category, and further points to the
lack of case law interpreting the rule. Response [#260] at 7-10. Well Master further argues
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that its supplemental discovery responses are not untimely under Rule 26(e) because
Flowco only recently set forth well-pleaded invalidity contentions, before which time the
priority date was not relevant to any claims in suit, and until now, Flowco never sought
Court assistance. Id. at 10-12. Finally, Well Master argues that exclusion of evidence is
not warranted because Flowco is attempting “to prevent Well Master from presenting
evidence that would establish priority dates for the asserted patents that are earlier than
certain alleged prior art, including the Sand Viper plunger.” Id. at 13. At the same time,
Well Master argues that Flowco shows no harm, and that Flowco can simply move to
amend its invalidity contentions by showing good cause. Id. at 12-14.
Because the Court finds that the Motion [#256] should be granted pursuant to Fed.
R. Civ. P. 26(e) and 37(c), it declines to consider whether exclusion is appropriate under
D.C.COLO.LPtR 5.
A. 	Rule 26(e)
The Court finds that Well Master’s supplementation of Interrogatory 1 was untimely
under Rule 26(e). Flowco served Interrogatory 1 and RFP 10 on February 21, 2022. Well
Master initially objected, in part based on relevance, but the Court’s May 24, 2022 Order
[#70] expressly rejected Well Master’s theory that invalidity and prior art were not at issue
because Flowco had not yet pleaded an invalidity defense. See Order [#70] at 3-4, 7. To
that end, Magistrate Judge Mix wrote, “despite the fact that an Answer had not yet been
filed, given Defendant’s assertion of invalidity in the Proposed Scheduling Order [#28][,]
[i]t is also beyond dispute that discovery regarding invalidity was permitted with leave of
court.” Id. at 3. Moreover, “such discovery was agreed, undertaken and ordered for at
least five months before Plaintiff filed its Motion to Strike.” Id. She observed that Well
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Master’s counsel, in conferral emails, had “agreed that ‘invalidity contentions are required
under the Scheduling Order[,]’ and contended that many of [Well Master’s] document
requests sought relevant information because they were directed to ‘identifying prior
potential art.’” Id. at 4 (modification in original).
Indeed, prompted by the May 24, 2022 Order [#70], Well Master supplemented
some of its discovery responses, most importantly RFP 10. Well Master stated that “[i]n
view of the Court’s Order [#70],” it was renewing its relevance objection to several
categories of documents, but it went on to “object[] to this request for production to the
extent that it seeks production of documentation that is already in Defendant’s possession
and/or that is publicly-available to Defendant.” Movant’s Appx. [#263-1] at 29. Specifically,
Well Master identified “documents showing the effective priority date of the patents-in-
suit [which] are available from the USPTO website.” Id.
Not until May 9, 2024, did Well Master supplement its response to Interrogatory 1,
finally asserting conception and earliest reduction to practice dates that significantly
preceded the filing of the respective patents—in some cases by years. See Movant’s
Appx. [#256-1] at 19-21. For example, Well Master states that the design of the Sand
Viper plunger incorporates the ‘865 and ‘729 patents and was conceived “around
September 2003,” that it was certainly reduced to practice by October 2004, when Well
Master began selling it, that U.S. Provisional App. No. 60/593,914 was filed on February
24, 2005, and that the ‘865 Patent was filed on February 8, 2006. Id. at 19-20. Well Master
states that the design of the Venturi plunger incorporates the ‘892 patent, was conceived
“around October 1, 2007,” and was certainly reduced to practice in the form of physical
prototypes by December 2009. Id. at 20-21. However, draft documents for a provisional
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patent application were not created until January 2010 and U.S. Provisional Application
No. 61/342,407 was filed on April 14, 2010. Id. at 21.
Well Master does not argue that it recently learned this information or that it has
acted diligently to disclose it. Instead, it argues that it was not obligated to disclose it “in
the absence of pled claims or defenses for patent invalidity”—an argument the Court had
rejected in its May 24, 2022 Order [#70]. Response [#260] at 12; but see Order [#70] at
6-7 (rejecting Well Master’s reliance on “unpublished cases outside of the Tenth Circuit
to contend that ‘Defendant is not entitled to take discovery on unpled claims or defenses’”
and declining request for a protective order preventing discovery on invalidity). By May
2022, the Court found that Defendant was plainly contesting the validity of the patents-in-
suit. Thus, the Court is not persuaded by Well Master’s suggestion that it was only
recently required to disclose information relevant to priority dates. See Response [#260]
at 12. Well Master’s reliance on an argument already rejected by this Court is not a
reasonable basis to withhold information or documents that were plainly responsive to
Flowco’s written discovery requests. Nor does Flowco’s lack of earlier complaints excuse
Well Master from its discovery obligations. Cf. Teashot, 2014 WL 485876, at *7 (noting a
party’s right to assume that the other side is complying with the rules).
Finally, the Court considers Rule 26(e) in light of the Federal Circuit’s admonition
that local patent rules are “designed specifically to ‘require parties to crystallize the
theories of their case early in the litigation’ so as to ‘prevent the “shifting sands” approach
to claim construction.’” O2 Micro Int’l Ltd., 467 F.3d at 1364 (quoting Atmel Corp., 1998
WL 775115, at *2). Here, Well Master appears engaged in a “shifting sands” approach to
priority dates. On July 8, 2022, Well Master straightforwardly stated that “documents
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showing the effective priority date of the patents-in-suit are available from the USPTO
website.” Movant’s Appx. [#263-1] at 29. Yet on May 9, 2024, it provided new information
and documents that were not publicly available and that contradicted priority dates shown
in the patent applications. Movant’s Appx. [#256-1] at 18-21. By affirmatively pointing
Flowco to public USPTO documents while in possession of documents and information
showing earlier priority dates, Well Master’s July 2022 supplemental response to RFP 10
knowingly (perhaps even intentionally) misled Flowco.
In summary, the Court is not persuaded by Well Master’s arguments that it owed
no duty to supplement under Rule 26(e). The Court finds that Well Master’s third
supplemental response to Interrogatory 1, including its contemporaneous disclosure of
documents showing earlier conception and reduction to practice, was untimely.
B. 	The Woodworker’s Supply Factors
Having found Well Master’s supplemental response and supplemental disclosures
untimely, the Court considers whether they were substantially justified or harmless,
specifically considering (1) the prejudice or surprise to Flowco; (2) Flowco’s ability to cure
the prejudice; (3) the extent to which introducing such evidence would disrupt the trial;
and (4) Well Master’s bad faith or willfulness. See Woodworker’s Supply, 170 F.3d 985,
993 (10th Cir. 1999).
Turning to the first prong, prejudice or surprise, the Court considers two cases that
applied Rule 26(e) in the context of shifting priority dates, Integra LifeSciences Corp. v.
Hyperbranch Med. Tech., Inc., No. 15-819-LPS-CJB, 2018 WL 3814614, at *2-3 (D. Del.
Mar. 23, 2018), and Elbit Sys. Land & C4I Ltd. v. Hughes Network Sys., LLC, No. 2:15-
cv-00037-RWS-RSP, 2017 WL 2651618, at *9-10 (E.D. Tex. June 20, 2017).
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In 	Elbit 	Sys., 	the 	plaintiff 	had 	consistently 	disclosed 	to 	the 	defendant 	and
represented to the court that the patent-in-suit’s priority date was its filing date, before
suddenly disclosing that it was entitled to a patent date nine months earlier, based on
earlier conception and reduction to practice. Elbit Sys., 2017 WL 2651618, at *9. The
court observed that the defendant’s “interrogatory understandably sought to commit [the
plaintiff] to a priority date.” Id. at *10. The court found that the change in priority date was
untimely under Rule 26(e) because it was undisputed that the plaintiff had the underlying
facts in its possession for more than three months but waited until the close of fact
discovery to disclose it. Id. The court precluded the plaintiff from presenting any evidence
or arguing that the patent’s priority date preceded its filing date. Id. Similarly, in Integra
LifeSciences, the plaintiffs supplemented interrogatory responses to identify a November
2001 priority date pursuant to a court order. See 2018 WL 3814614, at *2-3. More than a
year later, the plaintiffs suddenly asserted an earlier priority date of February 2001. Id. at
*3. The Court found the belated shift untimely and struck the earlier priority date, applying
the Third Circuit’s equivalent of the Woodworker’s Supply factors. Id.
In both cases, the district court emphasized the importance of a firm priority date
to a defendant developing its case. See Elbit Sys., 2017 WL 2651618, at *10 (finding
prejudice to the defendant, which had “justifiably developed invalidity positions under the
assumption that the ‘073 patent is entitled to a priority date no earlier than its filing date”);
Integra LifeSciences, 2018 WL 3814614, at *3 (“There can be no dispute that [the
defendant] would be prejudiced by such a shift [in the asserted priority date], as [its] entire
invalidity case against claim 10 of the ‘034 patent has relied on a priority date of November
9, 2001.”). Notably, in those cases, the shift in priority date was a matter of less than a
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year, while Well Master here attempts to shift priority dates several years earlier.
The Court finds that Well Master’s attempt to shift priority dates has caused Flowco
significant prejudice and surprise, given Well Master’s recently asserted conception dates
that predate filing dates by years. Cf. Motion [#256] at 10-11 (explaining the importance
of the priority date in searching for prior art and asserting that Flowco had relied on the
application date in conducting those searches); Reply [#263] at 9 (emphasizing the effort
and expense that has gone into developing Flowco’s invalidity case and the burden that
a “re-do of its prior art search” would impose).4 The Court finds that the first Woodworker’s
Supply factor weighs strongly in favor of exclusion.
As for the second factor, the Court finds that it will be difficult to cure the prejudice
to Flowco at this late stage in the litigation. The Court acknowledges that fact discovery
has not yet closed in this case, though deadlines are fast approaching following the
Court’s August 29, 2024 Claim Construction Order [#262]. However, Flowco has already
expended considerable time, effort, and expense building its invalidity case in reliance on
the patent application dates—reliance that Well Master reinforced by referring Flowco to
public USPTO filings. Cf. Movant’s App’x. [#263-1] at 29. Flowco explains that it asserted
invalidity contentions based on its search for prior art, based upon the priority date
associated with the patents’ filing, and that “[t]he possibility that Well Master could try to
4 Well Master surmises that Flowco’s claims of prejudice are contrived because Flowco “merely
asserts in conclusory fashion that it made unspecified decisions about its invalidity contentions
based on the earliest filing dates for the asserted patents” but presents no sworn testimony.
Response [#260] at 13-14. However, Well Master cites no authority holding that a party asserting
prejudice must substantiate that assertion with sworn testimony. The Court finds plausible
Flowco’s assertion that it relied on filing dates of the patents-in-suit when it conducted its prior art
search, and that its resulting prior art (and potentially its identified prior art) may well have differed
had it known of these newly alleged earlier conception and reduction to practice dates.
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pre-date a reference would have been one of the most important strategic considerations
in deciding which references to assert.” Motion [#256] at 11. Such prejudice is difficult to
measure, as priority dates commonly shape defendants’ entire invalidity cases. Cf. Elbit
Sys., 2017 WL 2651618, at *10 (noting that the defendant had developed its invalidity
positions based on a priority date no earlier than the filing date); Integra LifeSciences,
2018 WL 3814614, at *3 (noting that the defendant’s “entire invalidity case” against a
particular claim had relied on a particular priority date). Thus, the prejudice to Flowco
cannot be easily cured. See, e.g., Jama v. City & County of Denver, 304 F.R.D. 289, 301
(D. Colo. 2014) (finding that, while quantifiable monetary prejudice might be curable by
award 	of 	attorneys’ 	fees, 	“the 	more 	intangible 	types 	of 	prejudice” 	resulting 	from
inadequate Rule 26(e) supplemental disclosures could not be so easily cured). Moreover,
even if the Court were inclined to award monetary sanctions, a request Flowco has not
made, costs incurred due to Well Master’s untimely disclosure cannot readily be
segregated from other expenditures in this contentiously litigated case. The Court finds
that the second Woodworker’s Supply factor weighs in favor of exclusion rather than
monetary or other sanctions.
As for the third factor, disruption of trial, the Court acknowledges that trial has not
been set yet in this matter, but “there has been, and will continue to be, significant
disruption and delay to the prompt and expedient resolution of this matter as a direct
result of [Well Master’s] untimeliness.” Jama, 304 F.R.D. at 301. The priority dates issue
may significantly alter the parties’ trial strategy and tactics as well as any pretrial
settlement discussions. The Court finds that the third Woodworker’s Supply factor only
slightly favors exclusion.
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Finally, the Court considers the fourth factor, bad faith or willfulness. Willful failure
is “any intentional failure as distinguished from involuntary noncompliance.” Gocolay v.
N.M. Fed. Sav. & Loan Ass’n, 968 F.2d 1017, 1021 (10th Cir. 1992) (quoting In re
Standard Metals Corp., 817 F.2d 625, 628 (10th Cir. 1987)). On the record presented, the
Court hesitates to impute bad faith to Well Master, but it can firmly conclude that Well
Master willfully delayed disclosure of information it knew was both responsive to Flowco’s
discovery requests and highly relevant to the parties’ claims and defenses.
The timeline of this case supports the Court’s finding of willfulness. First, on March
15, 2022, Well Master represented that “no documents are believed to exist in Well
Master’s possession, custody, or control” that were responsive to D.C.COLO.LPtR 5(b),
which requires early disclosure of “[a]ll documents created on or before the application or
priority date (whichever is earlier) for each patent in suit that demonstrate each claimed
invention’s conception and earliest production to practice.” See Well Master’s First Supp.
Infringement Contentions [#46] at 6. Second, on July 8, 2022, Well Master supplemented
its response to RFP 10, affirmatively stating that “documents showing the effective priority
date of the patents-in-suit are available from the USPTO website.” Movant’s Appx. [#263-
1] at 29. These two representations could reasonably lull Flowco into believing that Well
Master had no additional documents in its possession and that Flowco could reasonably
rely on public USPTO filings to determine priority dates. As previously discussed, these
early representations omitted key information about priority dates, yet Well Master does
not assert that its May 9, 2024, supplement was prompted by new information. If Well
Master did not acquire this information during discovery, then it was in Well Master’s
possession all along. The Court can only draw one conclusion: Well Master intentionally
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withheld information and documents it knew were responsive to Flowco’s discovery
requests. The Court finds that the fourth Woodworker’s Supply factor weighs in favor of
exclusion.
Having weighed all four Woodworker’s Supply factors, the Court concludes that
the sanction of exclusion is appropriate and recommends that Defendant’s Motion [#256]
be granted pursuant to Fed. R. Civ. P. 26(e) and 37. Well Master should be precluded
from relying on any of the information or documents that were first disclosed in its Third
Supplemental Response to Interrogatory 1.
C. 	Local Patent Rule 5
The Court agrees with Well Master’s assertion that Flowco has not properly
developed its Local Patent Rule 5 argument with analysis and legal support. Cf.
Response [#260] at 8. However, because the Court finds that Well Master’s supplemental
response and supplemental production in response to Interrogatory 1 were untimely in
violation of Rule 26(e) and warrant exclusion under Rule 37(c), the Court need not
address the parties’ Rule 5 arguments. Cf. Seeley Int’l Pty Ltd., 2022 WL 3975005, at *6
(noting the “dearth of case law in the District of Colorado” construing D.C.COLO.LPtR 5).
IV. Conclusion
Based on the foregoing,
IT IS HEREBY RECOMMENDED that the Motion [#256] be GRANTED and that
Plaintiff/Counter Defendant Well Master be precluded from presenting any information or
documents related to priority dates that were first disclosed in its Third Supplemental
Response to Interrogatory 1.
IT IS FURTHER ORDERED that any party may file objections within 14 days of
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service of this Recommendation. In relevant part, Fed. R. Civ. P. 72(b)(2) provides that,
“within 14 days after being served with a copy of the recommended disposition, a party
may 	serve 	and 	file 	specific 	written 	objections 	to 	the 	proposed 	findings 	and
recommendations. A party may respond to another party’s objections within 14 days after
being served with a copy.” “[A] party’s objections to the magistrate judge’s report and
recommendation must be both timely and specific to preserve an issue for de novo review
by the district court or for appellate review.” United States v. 2121 E. 30th St., 73 F.3d
1057, 1060 (10th Cir. 1996). The objection must be “sufficiently specific to focus the
district court’s attention on the factual and legal issues that are truly in dispute.” Id. “[A]
party who fails to make a timely objection to the magistrate judge's findings and
recommendations waives appellate review of both factual and legal questions.” Morales-
Fernandez v. I.N.S., 418 F.3d 1116, 1119 (10th Cir. 2005).
Dated: December 2, 2024 	BY THE COURT:
Kathryn A. Starnella
United States Magistrate Judge
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