Integra LifeSciences Corp. et al v. HyperBranch Medical Technology, Inc

Filing 321

REPORT AND RECOMMENDATIONS regarding claim construction. Please note that when filing Objections pursuant to Federal Rule of Civil Procedure 72(b)(2), briefing consists solely of the Objections (no longer than ten (10) pages) and the Response to the Objections (no longer than ten (10) pages). No further briefing shall be permitted with respect to objections without leave of the Court. Objections to R&R due by 9/18/2017. Signed by Judge Christopher J. Burke on 8/30/2017. (mlc)

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF DELAWARE
INTEGRA LIFESCIENCES CORP.,
INTEGRA LIFESCIENCES SALES LLC,
CONFLUENT SURGICAL, INC., and
INCEPT LLC,
Plaintiffs,

v.
HYPERBRANCH MEDICAL
TECHNOLOGY, INC.,
Defendant.

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Civil Action No. 15-819-LPS-CJB

REPORT AND RECOMMENDATION
In this action filed by Plaintiffs Integra LifeSciences Corp., Integra LifeSciences Sales
LLC, Confluent Surgical, Inc. and Incept LLC (collectively, "Plaintiffs") against Defendant
HyperBranch Medical Technology, Inc. ("Defendant" or "HyperBranch"), Plaintiffs allege
infringement of United States Patent Nos. 6,566,406 (the "'406 patent"), 7,009,034 (the '"034
patent"), 7,332,566 (the '"566 patent"), 7,592,418 (the '"418 patent"), 8,003,705 (the '"3705
patent") and 8,535,705 (the '"5705 patent") (collectively, the "patents-in-suit" or "asserted
patents"). Presently before the Court is the matter of claim construction. The Court recommends
that the District Court adopt the constructions set forth below for the four terms discussed in this
Report and Recommendation. 1
I.

BACKGROUND

The parties submitted 18 terms or sets of terms for claim construction. (D.I. 248
at 2) The parties grouped the 18 terms/term sets into seven groups for purposes of the
Markman hearing. (Id. at 1-2) This Report and Recommendation addresses the final three
groups (i.e., Groups E, F and G). On July 27, 2017, August 4, 2017, and August 18, 2017, the
Court issued Reports and Recommendations regarding claim construction for the first four
groups of terms (which included 14 terms/term sets). (D.I. 307, 310, 316, 317)

The Court incorporates by reference herein the factual and procedural background about
this case and the patents-in-suit that was set out in the Court's July 27, 2017 Report and
Recommendation regarding claim construction. (D.I. 307 at 2-5)

II.

STANDARD OF REVIEW
The Court also incorporates by reference herein the discussion of general principles of

claim construction, as well as the legal standard relating to the definiteness requirement, which
were also set out in its July 27, 2017 Report and Recommendation. (Id at 5-7, 30-32)

III.

DISCUSSION
The Court takes up the four disputed terms in the order in which the parties addressed

them at the Markman hearing.

A.

"the first biocompatible precursor, the second biocompatible precursor, and
the third biocompatible precursor are reactable with each other to form a
crosslinked hydrogel" I "the first biocompatible precursor, the second
biocompatible precursor, and the third biocompatible precursor are
reactable with each other" 2

The term that is ultimately at issue here is "the first biocompatible precursor, the second
biocompatible precursor, and the third biocompatible precursor are reactable with each other to
form a crosslinked hydro gel[,]" which is found in certain claims of the '3 705 patent, including

2

These were presented to the Court as two terms, with the parties disputing
whether the language "to form a crosslinked hydrogel" should be included in the term to be
construed. (See, e.g., D.I. 230 at 8; D.I. 231 at 27 n.8) Plaintiffs sought the construction of the
term including this additional language "to ensure that the entire context of the claim could be
taken into account." (D.I. 230 at 8) During the Markman hearing, however, Defendant
acknowledged that it was "fine with including the 'to form a [crosslinked] hydrogel'" language in
the term to be construed. (Tr. at 179) Therefore, the Court will include that language in the term
to be construed here, and will thus provide a construction for "the first biocompatible precursor,
the second biocompatible precursor, and the third biocompatible precursor are reactable with
each other to form a crosslinked hydrogel."
2

claim 4. Plaintiffs propose that the term be construed to mean "the electrophilic functional
groups of the first biocompatible precursor are reactable with the primary amine functional
groups of the second and third biocompatible precursors to form a crosslinked hydro gel[,]" while
Defendant proposes that the term be construed to mean "the first biocompatible precursor, the
second biocompatible precursor, and the third biocompatible precursor each react with the other
two [to form a crosslinked hydrogel.]" (DJ. 230 at 8-9 (internal quotation marks omitted); D.I.
231 at 27) Claim 4 of the '3705 patent is set out below:
4. A kit comprising:
a first biocompatible precursor having at least two electrophilic
functional groups, and a second biocompatible precursor
comprising at least two primary amine functional groups, a third
biocompatible precursor comprising at least two primary amine
functional groups and, an applicator;
wherein the first biocompatible precursor, the second
biocompatible precursor, and the third biocompatible precursor
are reactable with each other to form a crosslinked hydrogel, are
resistant to enzymatic degradation, and at least one of the first,
second, or third biocompatible precursors comprises at least one
isolated hydrolytically degradable ester group;
wherein the applicator is configured to mix at least the first
precursor, the second precursor, and the third precursor to form a
crosslinked hydrogel in situ comprising covalent bonds formed by
reaction of the functional groups of the precursors and further
comprising the at least one isolated hydrolytically degradable ester
group;
wherein the hydro gel comprises a sufficient number of the at least
one isolated hydrolytically degradable ester groups in the
crosslinked hydrogel so that the crosslinked hydrogel is degradable
in less than about 180 days, is resistant to enzymatic degradation,
and is degradable by hydrolysis of the at least one isolated
hydrolytically degradable ester group; and
wherein the kit further comprises instructions that comprise
directions for making a hydrogel that is degradable in an amount of
time, with the amount of time being less than about 180 days.
('3705 patent, cols. 42:41-43:4 (emphasis added))
3

From this representative claim, we know, then, that the claims at issue require three
precursors-a first precursor, a second precursor, and a third precursor. (See D.I. 241 at 19)
Further, the claims require that the first precursor has electrophilic functional groups, and the
second and third precursors each have primary amine functional groups. (Id) The crux of the
dispute here is whether the construction for this term must require the second and third
biocompatible precursors to react with each other to form a crosslinked hydrogel, as Defendant
contends, or whether it instead requires the first biocompatible precursor to react with the second
and third precursors to form a crosslinked hydrogel, as Plaintiffs propose. (See D.I. 230 at 9; D.I.
231 at 27-28) Plaintiffs' proposal would not require the second and third precursors to react with
each other.
The person of ordinary skill in the art ("POSITA") would consider the claims as a whole,
Plaintiffs assert, and would know how to form a crosslinked hydrogel. (D.1. 230 at 9) Plaintiffs'
expert, Dr. Jimmy Mays, then explained that in conjunction with this knowledge, the POSITA
would additionally know that: "(1) electrophilic groups cannot react with other electrophilic
groups; and (2) that primary amine groups cannot react with other primary amine groups." (D.1.
242, ex. 14 at if 22; see also Tr. at 177) Thus, according to Plaintiffs, the POSITA would
understand the claims at issue to teach that the first precursor (with electrophilic functional
groups) reacts with the second and third precursors (both with primary amine functional groups)
in order to form a crosslinked hydrogel. (D.I. 230 at 9 (citing D.I. 122, ex. 6 at iii! 148-49); see

also D.I. 242, ex. 14 at if 21) With respect to the second and third precursors, Plaintiffs argue
that the POSITA would know that the claims do not specifically identify any functional groups of
the second and third precursors that would react with each other, and that those two precursors

4

thus "do not react together [to form a crosslinked hydrogel][.]" (D.I. 230 at 9) Plaintiffs argue
that this interpretation is in line with the patent's teaching that the claimed crosslinked hydrogels
of the invention "are made by reacting electrophilic functional groups with primary amine
functional groups[,]" (id.), and in Support, they cite to the following portion of the specification:
Some embodiments are methods for making a readily degradable
hydrogel by providing at least a first biocompatible precursor
having at least two electrophilic functional groups, providing at
least a second biocompatible precursor comprising at least two
primary amine functional groups; optionally providing at least a
third biocompatible precursor comprising at least two primary
amine functional groups; wherein the first precursor, the second
precursor, and the third precursor are reactable with each other to
form a crosslinked hydrogel, are resistant to enzymatic
degradation, and at least one of the first, second, or third precursors
includes at least one isolated hydrolytically degradable ester group.
And mixing at least the first precursor, the second precursor, and
optionally the third precursor to form a crosslinked hydrogel in situ
including covalent bonds formed by reaction of the functional
groups of the precursors and further including the at least one
isolated hydrolytically degradable ester group[.]
('3705 patent, cols. 1:58-2:7 (emphasis added)) 3
For its part, Defendant argues that Plaintiffs' proposal improperly reads out the
requirement in the claims that the first precursor, the second precursor, and the third precursor
"are reactable with each other." (D.I. 231at28; D.I. 243 at 18-19) Defendant points out that the
plain meaning of "'each"' is "'every one of two or more considered separately"' and that "'each
other"' means '"each one the other.'" (See D.I. 231at27 (citing D.I. 232, ex. 8 at 4)) The plain
language of the claims, Defendant asserts, thus requires that "each of the three precursors
considered separately must be able to react with each of the other two precursors." (Id. at 27-28)

3

The language in this portion of the specification largely mirrors that found in

claim 4 itself.
5

Defendant does not dispute that primary amine functional groups are not reactable with
each other to form a crosslinked hydrogel (and that, as a result, a second and third precursor that
each contained only "at least two primary amine functional groups" could not react with each
other to form a hydrogel). But Defendant argues that its proposed construction is nevertheless
sensible, and points to the "comprising" language found in the claim term at issue.
"Comprising," notes Defendant, is a term that means that the claim does not exclude additional
unrecited elements; it equates to "'including at least."' (D.I. 243 at 19 (citing Mars, Inc. v. HJ

Heinz Co., 377 F.3d 1369, 1375-76 (Fed. Cir. 2004)). Therefore, Defendant argues, since the
claims at issue recite second and third precursors each "comprising at least two primary amine
functional groups[,]" this means that "the second and third biocompatible precursors could have
other functional groups besides amines, which are indeed reactable with each other as the claim
requires." (Id; see also Tr. at 179 (Defendant's counsel asserting that "it's possible for the
second and third precursors to have both electrophilic and nucleophilic with some projected
groups in there as well and that they would be able to react with one another"))
The Court agrees with Defendant that, at least at first blush, the plain language of the
claims seems to require that each of the first, second and third precursors must each react with
every other precursor in order to form a crosslinked hydrogel. But with no dispute that two
precursors having primary amine functional groups are not capable ofreacting with each other to
form a hydrogel, the Court is ultimately persuaded that Plaintiffs' proposal should be adopted.
After all, the specific result called for by the claims is that a "crosslinked hydrogel" is to
be formed. The Court does not believe that Defendant's "comprising" argument is the answer
here, as it relies on unclaimed, unrecited, unidentified functional groups to be present in order to

6

help achieve the very result that is expressly called for by the claims. The United States Court of
Appeals for the Federal Circuit has explained that the term "comprising" has consistently been
interpreted to mean "that the listed elements ... are essential but other elements may be added."
Lochner Techs., LLC v. Vizio, Inc., 567 F. App'x 931, 939 (Fed. Cir. 2014) (emphasis added)

(internal quotation marks and citations omitted). In other words, in order to read on the claims,
every limitation must be present in the accused kit, and the import of the "comprising" language

is simply that a kit that includes additional elements not claimed may still infringe. (See Tr. at
178 (Plaintiffs' counsel explaining that "comprising" means that "there may be [another] group
in there, but that's not what you use to form a crosslinked hydrogel")) And here, it does not
make sense that (assuming Defendant's construction was correct) the patentees would have
drafted a method claim wherein-if the precursors contained nothing more than what was
absolutely required by the claim language-(1) the process of generating a crosslinked hydrogel
would require the second and third precursors to react with each other, but (2) their functional
groups cannot react with each other. Accordingly, the Court is persuaded that the POSITA
reviewing the claim and the specific groups recited therein will know that "to form crosslinked
hydrogels, you're reacting the electrophilic functional groups in the first precursor with the
primary amine functional groups of the second and third, and that's how you form a crosslinked
hydrogel." (Id. at 177-78)
For these reasons, the Court recommends that the term "the first biocompatible precursor,
the second biocompatible precursor, and the third biocompatible precursor are reactable with
each other to form a crosslinked hydrogel" be construed to mean "the electrophilic functional
groups of the first biocompatible precursor are reactable with the primary amine functional

7

groups of the second and third biocompatible precursors to form a crosslinked hydrogel."

B.

"free of amino acid sequences of more than about four residues in number"

Plaintiffs propose that the term "free of amino acid sequences of more than about four
residues in number" be construed to mean "[n ]ot having a sequence of amino acids of more than
about 4 amino acids[,]" while Defendant contends that the term is indefinite. (D.I. 230 at 17)
The term appears in certain claims of the '566 patent and the '418 patent directed to a hydrogel
that is "free of amino acid sequences of more than about four residues in number." ('566 patent,
cols. 39:36-38, 40:25-27, 41 :10-12; '418 patent, col. 39:34-36) It is undisputed that in this
context, the reference to "residues" is "another name for amino acids that have lost a water
molecule due to being bonded to another amino acid to form a sequence of amino acids." (D.I.
230at17; D.I. 243at19 n.2)
The core of Defendant's indefiniteness argument relates to the word "about" found in this
claim term. Defendant's expert, Dr. Anthony Lowman, explains that an amino acid sequence is
made up of a string of discrete amino acid residues. (D.I. 232 at if 154) Accordingly, the number
of amino acid residues present in a sequence would only be described as an integar value, and
cannot and would not be described by a fractional number (such as, for example, 3 %, 3.99, 4.01
or 4 Y4 amino acid residues). (Id.) For this reason, Defendant contends, the term "about" renders
the claims indefinite-" saying 'about four residues' has no precise meaning in the art because it
could mean three, four, five, and/or six residues." (Id.; see also D.I. 231 at 29 (explaining that
the POSITA "would not know how many amino acid residues would be required in order to
escape the claim. It is five? Is it six? Is it something more?"); D.I. 243 at 19) While
acknowledging that courts have found terms including the word "about" definite in situations

8

where the word is used to account for inherent measurement imprecision, (D.I. 231 at 29 (citing
GlaxoSmithKline Intellectual Prop. Mgmt. Ltd v. Sandoz, Inc., C.A. No. 11-1284-RGA, 2013
WL 1163759, at *2-4 (D. Del. Mar. 20, 2013)); D.I. 243 at 19-20), Defendant asserts that there is
no such imprecision at play here, where the number of residues are discrete, complete units, (D.I.
243 at 19-20). Defendant further argues that the intrinsic record sheds no light on the number of
amino acid residues that may be added to a sequence with four residues and still be in the scope
of the "about four residues in number" claim language. (D.I. 231 at 29)
Plaintiffs' briefing, unfortunately, did not provide much help with the dispute. Their
opening brief does not even address the issue, and instead is solely focused on arguing an
undisputed point: that the inclusion of the term "residues" in the claim does not render it
indefinite. (D.I. 230 at 17; see also D.I. 243 at 19 n.2 (Defendant responding that its "dispute is
not with the meaning of 'residues[]"')) In their answering brief, Plaintiffs first retorted that
Defendant's argument relating to "about" "disregards the overwhelming number of cases that
have found the term 'about' definite[.]" (D.I. 241 at 8 (citing cases)) As for the facts ofthis
case, Plaintiffs then asserted that:
Here the '566 prosecution history and specification makes clear that
"free of amino acid sequences of more than about four residues ..
." is important for a hydrogel with an acceptable gel time in a
patient. See D.I. 233, Ex. 11, p. 16-17 (citing Example 15, which
references Fig. 12 and Fig. 11, as support for this limitation). Fig.
12 discloses gel times for di-lysine, tri-lysine and tetra-lysine,
which have 2, 3, and 4 residues respectively. See ['566 patent, col.]
34:50-67, Fig. 11, 12.

(Id at 8-9)
With regard to the "prosecution history" referenced in those two sentences, there the

9

patentees added claims containing the claim term at issue, (see D.I. 233, ex. 11 at 12, 15), and
they cited to "Figure 11, Example 15" in support of these new claims, (id. at 17). Example 15, in
turn, is directed to measuring the change in gel time as a function of ester solution age. ('566
patent, col. 34:51-67) Example 15 also references Figure 12, which "shows the variation in
gelation time with the solution age of the electrophilic functional polymer." (Id., col. 4:47-48;

see also FIG. 12) And as for the reference to Figure 11, it "shows the variation in gelation time
with the number of amino groups for the reaction of 4 arm 10 kDa succinimidyl glutarate PEG
('SG-PEG') with di-, tri- or tetra-lysine." (Id., col. 4:43-46; see also FIG. 11)
The Court cannot see how any of this information elucidates the meaning of "about."
Plaintiffs' briefing does not directly explain the connection between "about" and these particular
references. (See D.I. 241 at 8-9) Nor did Plaintiffs cite to any expert testimony confirming that
the POSITA would glean the meaning of "about" from these references. (Id. )4
Thus, Plaintiffs' explanation in their answering brief really did not advance the ball. In
that explanation (set out above), Plaintiffs did note that the polymers represented in Figure 12
have 2, 3, and 4 residues respectively (i.e., that each has no more than 4 residues). (Id. at 9) But
the claim term does not recite a hydro gel that is free of amino acid sequences of more than four
residues in number-it recites one free of more than about four residues in number. After

4

Plaintiffs did submit a Rebuttal Declaration of their expert, Dr. Mays, "in
response to[] HyperBranch's [o]pening [c]laim [c]onstruction [b]riefl,]" (D.I. 242, ex. 14 at~ 2),
and Plaintiffs cited to that declaration in their answering brief in support of their assertion that
the meaning of this claim term is straightforward, (D.I. 241 at 8 (citing D.I. 242, ex. 14 at~ 56)).
Tellingly, however, while HyperBranch's opening brief with respect to this term focused on why
the word "about" renders the term indefinite, Dr. Mays' "response" for this term does not address
the "about" issue at all. Instead, Dr. Mays simply reiterates that the undisputed definition of
"residues" renders this term understandable to the POSITA. (D.I. 242, ex. 14 at~ 56)
10

reading the entirety of Plaintiffs' briefing, the question still remained unanswered: What does
the word "about" allow for and why is the word present in the claims?
When pressed about the issue during the Markman hearing, Plaintiffs directly asserted,
for the first time, that "about four" in this context means "four[,]" since "you can see [in looking
at Figure 12 that] right where you hit four that's where the gel times skyrocket up." (Tr. at 18182) In other words, Plaintiffs were now claiming that the term "free of amino acid sequences of
more than about four residues in number" means that there are "no more than four"
residues-"[i]t could not be five or six[.]" (Id at 182)
In one of their Markman hearing slides, Plaintiffs also cited to the Federal Circuit's
holding in Cohesive Tech., Inc. v. Waters Corp., 543 F.3d 1351, 1368 (Fed. Cir. 2008). Plaintiffs
were citing to that case for the proposition that "[t]he use of the word 'about' avoids a strict
numerical boundary to the specified parameter. Its range must be interpreted in its technological
and stylistic context." (Plaintiffs' Claim Construction Presentation, Slide 72 (certain internal
quotation marks omitted)) And then Plaintiffs asserted in the slide that the '566 patent and
specification "make clear what the technological and stylistic context 'about' is used in[.]" (Id)
But by way of further explanation as to what that "context" is, Plaintiffs simply pasted the chart
of Figure 12 onto the slide, and went on to state that it depicts the "[e]xemplary effect of number
of specific amino acid sequences (2, 3, or 4) on gel times for forming specific exemplary
hydrogels (See description of Example 15)." (Id)
These arguments at the Markman hearing (unsupported by any citation to expert
testimony) also did not clear up the uncertainty relating to the use of "about" in the claims. For
one thing, as Defendant retorted, Plaintiffs' position that "about four" means "four" reads the
11

term "about" right out of the claims. (Tr. at 184) In similar situations, courts have rejected
constructions that would render terms of degree such as "about" meaningless. See, e.g., Messer
v. Ho Sports Co., No. CV 06-826-PK, 2007 WL 2011210, at *10 (D. Or. July 9, 2007) (rejecting

the parties' proposal to construe '"approximately one fourth to one fifth"' to mean "'no less than
one fifth and no greater than one fourth"' as that proposal "ignore[s] the presence of the word
'approximately', which the parties would treat as meaningless (or as having the same meaning as
'precisely"')); Crown Packaging Tech., Inc. v. Rexam Beverage Can Co., 486 F. Supp. 2d 366,
381-82 (D. Del. 2007) (rejecting the defendant's proposal to construe "between about 20° and
about 60°" to mean "'[b]etween 20° and 60°"' as that proposal "elides the word 'about' from the
claim language"); Novartis Pharms. Corp. v. Apotex Corp., No. 02Civ.8917(KMW)(HBP), 2006
WL 626058, at *9 (S.D.N.Y. Mar. 13, 2006) (rejecting defendant's proposal to construe "about"
to mean "'limited to the precise lower and upper limits of the recited range"' as such a
construction "would render the term 'about' meaningless"); cf Merck & Co., Inc. v. Teva
Pharms. USA, Inc., 395 F.3d 1364, 1369-70 (Fed. Cir. 2005) (reversing the district court's

construction of "about" to mean "exactly" where the intrinsic evidence did not "redefine 'about'
to mean 'exactly' in clear enough terms to justify such a counterintuitive definition of 'about"').
Moreover, Plaintiffs' suggestion in its slide to the effect that Figure 12 somehow sheds
light on the issue-in that the figure purportedly depicts the "[e]xemplary effect of number of
specific amino acid sequences (2, 3, or 4) on gel times for forming specific exemplary
hydrogels"-was also unhelpful. That figure does little to explain why the term "about" was
included in these claims, which (if the presence of "about" were not considered) would otherwise
already recite a hydro gel with amino acid sequences of no more than four residues.

12

In sum, the intrinsic record does not support an interpretation of the claim term that
would read the word "about" entirely out of the claims. And the entire record, including Dr.
Lowman's declaration, strongly indicates that a POSITA would be in the dark as to what "about"
is intended to mean in the context of these claims. 5 For these reasons, the Court agrees with
Defendant that there is clear and convincing evidence that the scope of the claims are not
discemable, and that the term "free of amino acid sequences of more than about four residues in
number" is indefinite in the context of these claims.

C.

"unbleached"

Plaintiffs propose that the term "unbleached" be construed to mean "[n]ot altered by light
to effectively become clear[,]" while Defendant proposes that the term be construed to mean
"[h]as not been bleached to remove its color[.]" (D.I. 230 at 26) The term is found in claim 12
of the '566 patent, which is set out below:
12. A method of preparing a composition suitable to coat a tissue
substrate of a patient, the method comprising:
mixing reactive precursor species comprising nucleophilic
functional groups, reactive precursor species comprising
electrophilic functional groups, and at least about 0.1 mg/ml of an
5

This is an instance where, in the Court's view, it is appropriate to resolve the
definiteness dispute at the claim construction stage. The issue here ("What does 'about' mean?")
was and is a discrete one. It is also an issue that (as the case law cited above demonstrates) is not
unfamiliar in patent law. And this is a situation where, despite having multiple opportunities to
bring further clarity to the record, Plaintiffs did not do so during the briefing process, nor during
the Markman hearing. In contrast, Defendant set out its position clearly, and supported it with
expert testimony. Ultimately, it is fair and appropriate to resolve this legal question at this stage.
See, e.g., Jntegra Lifesciences Corp. v. HyperBranch Med Tech., Inc., Civil Action No. 15-819LPS-CJB, 2017 WL 3331739, at* 1 n.2 (D. Del. Aug. 4, 2017) (concluding that the issue of
whether a claim term was indefinite was "ripe" for consideration where Plaintiffs did not
specifically identify how additional time would better advance the record, the parties' experts had
the opportunity to address the issue, and the parties had a "full, fair opportunity" to litigate the
issue) (internal quotation marks and citation omitted).
13

unbleached visualization agent such that the nucleophilic
functional groups react with the electrophilic functional groups to
form covalent bonds and crosslink the reactive precursor species
after the mixing to form a covalently crosslinked biodegradable
hydrogel contacting the tissue substrate and having an interior and
an exterior, with the exterior having at least one tissue substrate
coating surface and the visualization agent being at least partially
disposed within the interior,
wherein the hydrogel comprises chemical groups that are prone to
aqueous hydrolysis and is thereby degradable in vitro by exposure
to aqueous solution, and
wherein the visualization agent has a predetermined concentration
that indicates a predetermined thickness of the hydro gel as
deposited on substrate.
('566 patent, cols. 39:50-40:3 (emphasis added)) The crux of the dispute between the parties
with respect to the term "unbleached" is whether it means that the visualization agent has not
been altered by light to become clear (with clarity not being strictly equated with the absence of
color), as Plaintiffs contend, or whether it means that the visualization agent has not been
bleached to remove its color, as Defendant argues. (See D.I. 241 at 20; D.I. 243 at 20; Plaintiffs'
Claim Construction Presentation, Slide 74) 6 The Court finds that the intrinsic evidence best
aligns with Defendant's proposal.
In support of their proposed construction, Plaintiffs point to the prosecution history of the

'566 patent. (D.I. 230 at 26) Plaintiffs explain that the claim limitation reciting an "unbleached
visualization agent" was added to overcome a rejection based on United States Patent No.
5,410,016 ("Hubbell et al."), and that in the amendment, the patentees explained the following:

6

Plaintiffs assert that Defendant's proposed construction should be rejected as it
does not address any fundamental dispute between the parties regarding the scope of the claim.
(D.1. 230 at 27; D.I. 241 at 20) The Court does not understand how this is so, as the parties'
competing proposals do, in fact, underscore the dispute between them: is an unbleached
visualization agent one that has not had its color removed, or one that has not effectively become
clear?
14

A copy of an affidavit previously submitted in the parent case U.S.
Ser. No. 10/010,075, now U.S. Pat. No. 7,009,034 (Affidavit) is
hereby submitted under 37 C.F.R. § 1.132. The Affidavit is a
declaration of Amarpreet Sawhney, []who is an inventor on
the Application and also an inventor on the Hubbell et al,
reference.
As explained in the Affidavit, Hubbell et al., in general, uses
dyes (such as Eosin Y or Methylene Blue) as part of a
photoinitiation process that requires exposure to light
wavelengths that bleach the dyes. When bleached, they no
longer serve the function of visualization agents. This testimony
is corroborated by Gruber et al. (attached) and the FDA FOCAL
SEAL approval materials (attached) that describe how the dyes
change from colored to clear during use.

A dye that has been bleached as in the Hubbell et al. process
yields a product that is not a visualization agent because it has
effectively lost its coloration. Indeed, the term "unbleached"
is, strictly speaking. superfluous since a bleached dye can not
be a visualization agent and a visualization agent is
unbleached. Even if some concentration of unbleached dye
were to remain after the bleaching process, the concentration
of unbleached dye would not be the concentration of
visualization agent that is claimed. A bleached dye is not the
claimed visualization agent. Accordingly, withdrawal of this
rejection is requested.
(D.I. 233, ex. 11 at 18 (cited in D.I. 230 at 26-27) (with the emphasis above matching that used in
Plaintiffs' citation))
In the Court's view, this passage actually supports Defendant's proposal. The patentees
were there attaching documentation that describes how the substances undergoing the bleaching
process "change from colored to clear"-i.e., these dyes have had their color removed. In other
words, it is evident from this passage that when the patentees referred to "clear" here, they meant
"colorless." This is reiterated when the patentees explain that a dye that has been bleached as in
Hubbell et al. is not a visualization agent "because it has effectively lost its coloration"-i.e., it

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has had its color removed.
Other portions of the prosecution history of the '566 patent (and related patents)
underscore that a visualization agent that has been "bleached" is one that has had its color
removed. (See Tr. at 184-85 (Defendant's counsel asserting that "[t]here are numerous
statements in [the intrinsic evidence] ... about bleached, removing color or visualization
agent[s] losing their color and, therefore, not a visualization agent")) At least three pieces of
such evidence further bolster Defendant's case.
The first relates to the Examiner's further rejection of the claim that ultimately issued as
claim 12 of the '566 patent, on the ground that the claim was unpatentable over Hubbell et al.
combined with other prior art references. (D.I. 232, ex. 3 at HBMT0407020) In responding to
this rejection, and in explaining why there would be no reasonable expectation of success in
combining the references to arrive at the patented invention, the patentees explained that "a dye
that participates in the photo-reaction process [as in Hubbell et al.] could be bleached and

thereby made colorless ... and not be useful for establishing the claimed predetermined
thicknesses[] or claimed visually observable changes[.]" (Id. at HBMT0407058 (emphasis
added))
Second, the patentees drew this same connection between the bleaching process and
removing color from a substance during prosecution of the '034 patent. That patent's claims
recite a "visualization agent," and in overcoming a rejection based on Hubbell et al., the
patentees submitted the above-referenced affidavit of Dr. Sawhney, and explained that:
Dr. Sawhney, in the Affidavit, states that a [POSITA] would
understand that the dyes used as photoinitiators in the
photoinitiation process of the Hubbell et al. would be bleached
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during that process . . . . The PMA is provided as further support.
The PMA states that the FOCAL [] SEAL, which is covered by
[Hubbell et al.], has a pink color before photoinitiation and is
colorless after photoinitiation. The pink color is contributed by the
dye EOSIN Y, which is a photoinitiator that is consumed by the
photopolymerization process.

(Id, ex. 2 at HBMT0406639-40 (emphasis added)) In the referenced Affidavit, Dr. Sawhney
explains that FOCAL SEAL uses a dye that imparts a red or pinkish color, and this dye "becomes
bleached during the photopolymerization process to produce a clear hydrogel"-i.e., a hydrogel
that has had the red/pinkish color removed. (D.I. 247, ex. J at HBMT0406962)
Third, the Court notes that when the applicants added the "unbleached" limitation to the
'566 patent, they explained that "[c]laim 1 was amended to recite at least about 0.1 mg/ml of an
unbleached visualization agent as supported at, e.g., page 13 lines 11-15, with the agent being
unbleached because it is in the final hydrogel composition and serve[s] the function of being
visualization agent which must be visible, i.e., unbleached." (D.I. 232, ex. 3 at HBMT0406948)
The above-referenced portion of the specification ("page 13 [,] lines 11-15"), in tum, explains
that preferred biocompatible visualization agents consisting of blue dyes are preferably present in
the final precursor at a concentration of more than 0.05 mg/ml, and more preferably in a
concentration range of 0.1 to 4.0 mg/ml, although greater concentrations may potentially be used,
up to the limit of solubility of the visualization agent. (Id at HBMT0406788) It goes on to say
that such "concentration ranges were found to give a color to the hydrogel that was desirable
without interfering with crosslinking times[.]" (Id) This "support[]" for the unbleached
limitation is all about a colored (i.e., unbleached) visualization agent-that is, a visualization
agent that "has not been bleached to remove its color."

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For these reasons, the Court recommends that "unbleached" should be construed to mean
"has not been bleached to remove its color."
IV.

CONCLUSION
For the foregoing reasons, the Court recommends that the District Court adopt the

following constructions:
1.

"the first biocompatible precursor, the second biocompatible precursor, and the

third biocompatible precursor are reactable with each other to form a crosslinked hydrogel"
should be construed to mean "the electrophilic functional groups of the first biocompatible
precursor are reactable with the primary amine functional groups of the second and third
biocompatible precursors to form a crosslinked hydrogel"
2.

"free of amino acid sequences of more than about four residues in number"

is indefinite
3.

"unbleached" should be construed to mean "has not been bleached to remove its

color"
This Report and Recommendation is filed pursuant to 28 U.S.C. § 636(b)(l)(B), Fed. R.
Civ. P. 72(b)(l), and D. Del. LR 72.1. The parties may serve and file specific written objections
within fourteen (14) days after being served with a copy of this Report and Recommendation.
Fed. R. Civ. P. 72(b)(2). The failure of a party to object to legal conclusions may result in the
loss of the right to de novo review in the district court. See Henderson v. Carlson, 812 F.2d 874,
878-79 (3d Cir. 1987); Sincavage v. Barnhart, 171 F. App'x 924, 925 n.l (3d Cir. 2006).
The parties are directed to the Court's Standing Order for Objections Filed Under Fed. R.
Civ. P. 72, dated October 9, 2013, a copy of which is available on the District Court's website,

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located at http://www.ded.uscourts.gov.

Dated: August 30, 2017
Christopher J. Burke
UNITED STATES MAGISTRATE JUDGE

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