SunPower Corporation v. PanelClaw Inc.

Filing 148

MEMORANDUM ORDER regarding Claim Construction. Signed by Judge Mary Pat Thynge on 8/31/16. (cak)

IN THE UNITED STATES DISTRICT COURT
FOR THE DISTRICT OF DELAWARE
SUNPOWER CORPORATION,
Plaintiff,
v.
PANELCLAW, INC.,
Defendant.

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C. A. No. 12-1633-MPT

MEMORANDUM ORDER
I.

INTRODUCTION
This is a patent case. On December 3, 2012, SunPower Corporation

(“SunPower” or “plaintiff”) filed suit alleging PanelClaw, Inc. (“PanelClaw” or
“defendant”) infringes U.S. Patent Nos. 5,505,788 (“the ‘788 patent”) and RE38,988
(“the ‘988 patent”).1 SunPower amended its complaint on January 24, 2013, and again
on April 15, 2013.2 PanelClaw filed its answer and counterclaims to the Second
Amended Complaint on May 29, 2013.3 A Markman hearing was held on June 3, 2016.
This Memorandum Order sets forth the court’s construction of the disputed terms of the
‘988 patent.4
The ‘988 patent, titled “Lightweight, Self-Ballasting Photovoltaic Roofing

1

D.I. 1.
D.I. 5 (First Amended Complaint); D.I. 16 (Second Amended Complaint).
3
D.I. 18.
4
The court previously issued a summary judgment Memorandum and Order
finding non-infringement of the ‘788 patent. D.I. 88. Subsequently, plaintiff filed a
Motion for Clarification and Reconsideration of the Court’s April 1, 2016 Memorandum
and Order. D.I. 92. The court recently ruled on that motion. D.I. 137.
2

Assembly,” is a re-issue of U.S. Patent No. 5,746,839 that issued in 1998. The ‘988
patent was filed in 2003, issued in 2006, and expired in early 2016. The invention
“generally relates to a photovoltaic roofing assembly, and in particular to a lightweight
photovoltaic roofing assembly requiring no roofing penetrations and which resists wind
up-lift due to specialized component geometry and by acting as an integral assembly.”5
The Abstract of the ‘988 patent recites:
A photovoltaic roofing assembly comprises a roofing membrane (102), a
plurality of photovoltaic modules (104, 106, 108) disposed as a layer on
top of the roofing membrane (102), and a plurality of pre-formed spacers,
pedestals or supports (112, 114, 116, 118, 120, 122) which are
respectively disposed below the plurality of photovoltaic modules (104,
106, 108) and integral therewith, or fixed thereto. Spacers (112, 114, 116,
118, 120, 122) are disposed on top of roofing membrane (102).
Membrane (102) is supported on conventional roof framing, and attached
thereto by conventional methods. In an alternative embodiment, the
roofing assembly may have insulation block (322) below the spacers (314,
314', 315, 315‘). The geometry of the preformed spacers (112, 114, 116,
118, 120, 122, 314, 314‘, 315, 315') is such that wind tunnel testing has
shown its maximum effectiveness in reducing net forces of wind uplift on
the overall assembly. Such construction results in a simple, lightweight,
self-ballasting, readily assembled roofing assembly which resists the
forces of wind uplift using no roofing penetrations.6
II.

CLAIM TERMS AT ISSUE
The parties agree that the term “fluidly coupling” means “allowing a fluid, such as

air, to pass through and around allowing the open region below a module to connect
with the upper surface of the module.”7 The court adopts the parties’ construction of
that term. The following terms are in dispute.
1.

Spacer Terms: spacer; variable-height spacer
5

‘988 patent, 1:22-26.
‘988 patent, Abstract.
7
D.I. 83, Ex. A at 6.
6

2

Representative claim 18 of the ‘988 patent recites:
1. A photovoltaic assembly comprising:
A building rooftop;
a photovoltaic module having sides and having upper and lower
surfaces; and
a spacer secured to the lower surface of the photovoltaic module
and supported by the building rooftop;
said spacer sized and configured to define:
an open region beneath said lower surface, said open region
extending between and in contact with the lower surface and
in direct contact with the building rooftop, and
including access openings formed therein for fluidly coupling
said open region to said upper surface;
said access openings extending along at least two sides of said
photovoltaic module;
whereby wind uplift forces are resisted when said photovoltaic
assembly is mounted to the building rooftop.9
Representative claim 36 of the ‘988 patent recites:
36. A photovoltaic roofing assembly comprising:
a plurality of photovoltaic assemblies, each said photovoltaic assembly
comprising:
a photovoltaic module having upper, lower, and lateral sides and
having upper and lower surfaces; and
a variable-height spacer secured to the lower surface of the
photovoltaic module so to orient said photovoltaic module at an
angle with said lateral sides extending downwardly from said upper
side to said lower side, said angle being about 5E-30E from
8
9

As incorporated in and part of asserted dependent claims 17, 18, 58, and 73.
‘988 patent, claim 1 (emphasis added).
3

horizontal;
said spacer sized and configured to define:
a tapered open region beneath said lower surface; and
access openings along said upper and lower sides fluidly coupling
said open region to said upper surface;
whereby wind uplift forces are resisted when said photovoltaic
assembly is mounted to a support surface; and
means for interengaging adjacent photovoltaic assemblies into an array of
photovoltaic assemblies, said array defining a perimeter.10
Plaintiff’s proposed construction for “spacer” is “structure(s) providing support for
the module(s), ensuring consistent spacing between the modules.” Its proposed
construction for “variable-height spacer” is “a spacer that supports the module or
modules at an incline.”
Defendant’s proposed construction for “spacer” is “a single structure that
supports a module.” Its proposed construction for “variable-height spacer” is “a single
structure that supports a module at an incline.”
The parties agree these terms at least require a structure that provides support
for the module and that a “variable-height spacer” supports a module at an incline. The
primary disagreement is whether the “spacer” in these terms is limited to a “single
structure.”
Claims 1 and 36 recite “a spacer” and “a variable-height spacer.” The Federal
Circuit:
has repeatedly emphasized that an indefinite article “a” or “an” in patent
10

‘988 patent, claim 36 (emphasis added).
4

parlance carries the meaning of “one or more” in open-ended claims
containing the transitional phrase “comprising.” That “a” or “an” can mean
“one or more” is best described as a rule, rather than merely as a
presumption or even a convention. The exceptions to this rule are
extremely limited: a patentee must evince[ ] a clear intent to limit “a” or
“an” to “one.” The subsequent use of definite articles “the” or “said” in a
claim to refer back to the same claim term does not change the general
plural rule, but simply reinvokes that non-singular meaning. An exception
to the general rule that “a” or “an” means more than one only arises where
the language of the claims themselves, the specification, or the
prosecution history necessitate a departure from the rule.11
The court finds that the intrinsic record does not necessitate departure from the
rule and the spacer terms are not limited to a single structure. Claims 1 and 36 recite “a
spacer” and “a variable-height spacer.” Defendant points to other claims, e.g.,
dependent claim 14 and independent claim 80, as requiring “a plurality” of “spacers” to
support its position that the disputed terms are limited to a single structure. The Federal
Circuit noted:
There is presumed to be a difference in meaning and scope when different
words or phrases are used in separate claims. To the extent that the
absence of such difference in meaning and scope would make a claim
superfluous, the doctrine of claim differentiation states the presumption
that the difference between claims is significant.12
Here, however, there is a difference in claim scope between claims 1 and 36 and
claims 14 and 80 that makes no claim superfluous. While claims 1 and 36 would cover
embodiments having “one or more” spacers, claims 14 and 80, which require a plurality
of spacers, would only cover embodiments having multiple spacers. For instance,

11

Baldwin Graphic Sys., Inc. v. Siebert, Inc., 512 F.3d 1338, 1342-43 (Fed. Cir.
2008) (emphasis added) (alteration in original) (internal quotation marks and citations
omitted).
12
Comark Comms., Inc. v. Harris Corp., 156 F.3d 1182, 1187 (Fed. Cir. 1998)
(citation and quotation marks omitted).
5

figures 1C and 1D illustrate an embodiment described as having a single spacer
supporting a module.13 In contrast, figures 1A and 1B illustrate an embodiment
described as having a plurality of spacers.14 Because claims 1 and 36 can cover
embodiments having “one or more” spacers, those claims would cover each of the
embodiments illustrated by those figures, whereas claims 14 and 80 would only cover
the embodiment having a plurality of spacers illustrated in figures 1A and 1B.
Because none of the intrinsic evidence, or arguments by defendant, demonstrate
a necessity to deviate from the rule that “a” or “an” means “one or more,” the court
adopts plaintiff’s proposed constructions that “spacer” means “structure(s) providing
support for the module(s), ensuring consistent spacing between the modules”15 and
“variable-height spacer” means “a spacer that supports the module or modules at an
incline.”
2.

access openings
Both representative claims 1 and 36, cited above are relevant to the analysis of

the disputed term “access opening.” Specifically, “access openings extending along at
least two sides of said photovoltaic module” in claim 1 and in claim 36, the language

13

‘988 patent, Figs. 1C, 1D; 4:65-5:18.
‘988 patent, Fig. 1A, 1B; 4:15-46.
15
The specification supports the final language of plaintiff’s proposed
construction. Describing Figure 2B, the specification explains “[s]pacers 220, 220', 222,
222', 226, 226', 228, 228' also ensure consistent spacing between the PV modules
. . . .” ‘988 patent, 6:19-20 (emphasis added). The court also notes claim 3 of the ‘988
patent recites: “The assembly according to claim 2 wherein said spacer comprises
multiple spacer elements, at least one element secured to said lower surface along
each of said at least three sides. ‘988 patent, claim 3 (emphasis added). At the
Markman hearing, defendant agreed that a single spacer can be made up of multiple
elements. Markman Tr. at 33:1-6.
14

6

“access openings along said upper and lower sides fluidly coupling said open region to
said upper surface.”
Plaintiff’s proposed construction is “openings connecting the upper surface of the
photovoltaic module(s) to the open region beneath the photovoltaic module(s).”
Defendant’s proposed construction is “openings in the spacer along the sides of
the module.”
Defendant states the parties’ dispute regarding this term is whether the openings
must be in the “spacer” or whether any opening that connects the upper surface of the
module to the open region beneath the module meets the limitation.16 Defendant’s
proposed construction, however, is largely predicated on the same argument it made
with regard to the spacer terms, i.e., that the claims are limited a single spacer, an
argument the court rejects.
Defendant cites an embodiment where the access opening is in a spacer: “[i]n
Figs. 1C and 1D spacer 132 is shown pre-formed with openings 150, 152 which enable
free air exchange at the low and high sides of the module 106 to the underside of the
module 106.”17 In construing the spacer terms, however, the court determined claims 1
and 36 were not limited to only covering that embodiment.
Claim 36 requires the spacer “to define” an “open region” below the “lower
surface” of the module and “access openings” along the “upper and lower sides” of the
module that “fluidly coupl[es]” the “open region” to the “upper surface” of the module.18
16

D.I. 111 at 36-37.
‘988 patent, 4:66-5:2.
18
Defendant focuses on the language of claim 1, “access openings formed
therein,” which is not included in claim 36. At the Markman hearing, defendant stated
17

7

The embodiment illustrated in Figure 1B has access openings that are not in a
spacer. Also, the specification does not limit access openings to those in a particular
spacer. In the “Summary of the Invention,” the specification states “[t]he spacers are
preferably pre-formed and are sized and configured to provide passageways beneath
the photovoltaic modules extending from at least two sides of the modules to reduce
uplift forces on the modules.”19 “Spacers 314, 315' preferably follow the periphery of
module 306 while leaving openings to the interior of tile 301 that are between 5% to
50% of the edge length of module 306.”20 “Poor performance is experienced where
there is continuous blocking of the interior cavity around the perimeter of the module.
Optimal holddown occurs where the modules have some small degree of opening to the
interior cavity, in the range of 10%-30%.”21
Consequently, the court adopts plaintiff’s proposed construction of “access
openings” to mean “openings connecting the upper surface of the photovoltaic
module(s) to the open region beneath the photovoltaic module(s).”
3.

whereby wind uplift forces are resisted
Representative claim 36 of the ‘988 patent includes the disputed term “whereby

wind uplift forces are resisted when said photovoltaic assembly is mounted to a support

that neither party contends there is a difference in claim scope because of that
difference in claim language. Markman Tr. at 40:1-3. Because the court’s construction
of the spacer terms includes claim coverage of embodiments not specifically requiring
the access opening be in a spacer itself, and the parties’ agreement that the scope of
claims 1 and 36 are the same, the court rejects defendant’s argument based on this
difference in language between those two claims.
19
‘988 patent, 2:47-51 (emphasis added).
20
‘988 patent, 6:59-62 (emphasis added).
21
‘988 patent, 7:2-6 (emphasis added).
8

surface” (the “Whereby Clause”).
Plaintiff’s proposed construction is “whereby wind uplift forces are resisted in
excess of the resistance provided by the weight of the assembly alone.”
Defendant argues this term cannot be construed and is invalid pursuant to 35
U.S.C. § 112.
Like claim construction, “[i]ndefiniteness is a question of law . . . .”22 “Because a
patent is presumed to be valid, the evidentiary burden to show facts supporting a
conclusion of invalidity is one of clear and convincing evidence.”23 “[A] patent is invalid
for indefiniteness if its claims, read in light of the specification delineating the patent,
and the prosecution history, fail to inform, with reasonable certainty, those skilled in the
art about the scope of the invention.”24 “[A] claim must be ‘sufficiently definite to inform
the public of the bounds of the protected invention, i.e., what subject matter is covered
by the exclusive rights of the patent.’”25 Attorney argument is generally insufficient to
demonstrate invalidity.26
22

H-W Tech., L.C. v. Overstock.com, Inc., 758 F.3d 1329, 1332 (Fed. Cir. 2015)
(citing Exxon Research & Eng’g Co. v. United States, 265 F.3d 1371,1376 Fed. Cir.
2001)).
23
Young v. Lumenis, Inc., 492 F.3d 1336, 1345 (Fed. Cir. 2007) (citing AK Steel
Corp. v. Sollac & Ugine, 344 F.3d 1234, 1338-39 (Fed. Cir. 2003)).
24
Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 2124 (2014).
25
Ancora Techs., Inc. v. Apple, Inc., 744 F.3d 732, 737 (Fed. Cir. 2014) (quoting
Halliburton Energy Servs., Inc. v. M–I LLC, 514 F.3d 1244, 1249 (Fed. Cir. 2008)).
26
See, e.g., Research Frontiers, Inc. v. E Inc. Corp., C.A. No. 13-1231-LPS,
2016 WL 1169580, at *22 (Mar. 24, 2016) (“[T]he court believes an indefiniteness
challenge should be addressed with the benefit of a more developed record. Here,
declining to address [defendant’s] argument is appropriate, as [defendant] provides only
attorney argument in support of its position, which is insufficient to establish
indefiniteness.” (citing WesternGeco LLC v. ION Geophysical Corp., 876 F. Supp. 2d
857, 875 (S.D. Tex. 2012) (“Defendant’s unsupported attorney argument fails to prove
indefiniteness by clear and convincing evidence.”); Cacace v. Meyer Mktg. Co., Ltd.,
9

Defendant previously filed an early motion for summary judgement urging the
court, inter alia, to find the asserted claims of the ‘988 patent invalid based on its
assertion that the Whereby Clause was indefinite.27 The court declined to make that
finding and denied defendant’s motion on that issue.28 At the current Markman stage,
defendant reiterates much of its summary judgment arguments, with minimal additional
evidence, in support of its indefiniteness contentions. Therefore, the court again
declines to accept defendant’s indefiniteness argument and finds that one of skill in the
art examining the intrinsic evidence would understand that the Whereby Clause means
“whereby wind uplift forces are resisted in excess of the resistance provided by the
weight of the assembly alone.”29
812 547, 561 (S.D.N.Y. 2011) (explaining that “mere attorney argument is insufficient to
establish invalidity based in indefiniteness”)).
27
D.I. 69.
28
D.I. 88.
29
This construction is supported by the specification. See, e.g., ‘988 patent 3:6164 (“FIGS. 1A to 1D show views of one embodiment of the invention with spacers
resting directly on a roofing membrane and with spacer geometry designed to minimize
wind uplift on the overall assembly.”); ‘988 patent, 4:66-5:6 (“In FIGS. 1C and 1D spacer
132 is shown pre-formed with openings 150, 152 which enable free air exchange at the
low and high sides of module 106 to the underside of the module 106. Such free air
exchange with the spacer geometry shown had been determined through wind-tunnel
testing to aid in the instantaneous equilibration of air pressures between the top and
bottom side of module 106, thus reducing net forces of wind uplift.”); ‘988 patent, 4:35:40 (“The assembly is lightweight (9.76-19.53 kg/sq. m or 2-4 pounds/sq. ft.) relative to
conventional roofing ballast (48.8-73.2 kg/sq. m or 10-15 pounds/sq. ft.) relying on a
combination of weights, edge to edge connection, and spacer geometry to resist the
forces of wind uplift.”); see also D.I. 75 (Declaration of Theodore Stathopoulos, Ph.D. at
¶¶ 20-23) (Stathopoulos opines the “essence of the invention” is that “its light weight
photovoltaic assemblies resist wind uplift not because of weight alone but because of
the aerodynamic features of the assemblies,” which one of skill in the art would
understand. He further opines the “fact that wind uplift forces are resisted by the
claimed assemblies not because of their weight alone but also because of the particular
structural elements of those claims is described in detail throughout the specification of
the ‘988 patent, and would be readily understood to be so by one of skill in the arts.
10

4.

Weight Terms: combined weight of about 2-4 (or 1.67-5) pounds per square foot;
plurality of PV assemblies has a weight of not more than about four pounds per
square foot
Representative claim 18 of the ‘988 patent recites:
18. The assembly according to claim 1 wherein said photovoltaic module
and spacer have a combined weight of about two to four [or 1.67-5]
pounds per square foot.30
Representative claim 40 of the ‘988 patent recites:
40. The assembly according to claim 36 wherein said plurality of
photovoltaic assemblies has a weight of no more than about four pounds
per square foot.31
Plaintiff originally proposed construing “combined weight of about 2-4 (or 1.67-5)

pounds per square foot” as “the distributed weight of the assembly over the surface
area covered by the assembly is about 2-4 (or 1.67-5) pounds per square foot.” During
briefing, it modified its proposed construction to “distributed weight over the surface
area covered by the assembly of about 2-4 (or 1.67-5) pounds per square foot.” Its
proposed construction of “plurality of PV assemblies has a weight of not more than
about four pounds per square foot” is “the distributed weight of the plurality of PV
assemblies over the surface area covered by the assemblies is not more than about
four pounds per square foot.”
Defendant argues these terms cannot be construed and are invalid pursuant to
35 U.S.C. § 112.

Also, the additional limitations recited in the asserted claims in this case would further
define the scope of the claims, including the resistance of wind uplift, to a person of
ordinary skill in the art.”).
30
‘988 patent, claim 18 (emphasis added); claims 58-66.
31
‘988 patent, claim 40 (emphasis added).
11

Defendant contends the issues with these terms are the question of what is
supposed to have a combined weight of “about” 2 to 4, or not more than “about” four,
pounds per square foot and that the patent purportedly provides no guidance as to what
an acceptable variance might be to avoid infringement.
The court finds defendant has not established, by clear and convincing evidence,
that these terms are indefinite due to a failure “to inform, with reasonable certainty,
those skilled in the art about the scope of the invention.”32 Other than attorney
argument, defendant offers no expert testimony supporting its position that these terms
are indefinite. To the extent that defendant’s argument rests on the assertion that the
asserted claims cover only the weight of a single spacer and a single module, the court
has rejected that interpretation. Additionally, at the Markman hearing, plaintiff
acknowledged that if additional components (e.g., perimeter ballast or windspoils) are
present, those components would be included in the claimed average weights.33
The Federal Circuit has noted that the term “‘about’ . . . is a descriptive term
commonly used in patent claims to ‘avoid a strict numerical boundary to the specified
parameter.’”34 The word “about,” however, “does not have a universal meaning in
patent claims, and . . . the meaning depends on the technological facts of the particular
32

Nautilus, 134 S. Ct. at 2124 (emphasis added).
Markman Tr. at 114:23-116:5; Plaintiff’s hearing presentation slide 36.
34
Ecolab, Inc. v. Evirochem, Inc., 264 F.3d 1358, 1367 (Fed. Cir. 2001) (quoting
Pall Corp. v. Micron Separations, Inc., 66 F.3d 1211, 1217 (Fed. Cir. 1995)); see also
Andrew Corp. v. Gabriel Elecs., Inc., 847 F.2d 819, 521-22 (Fed. Cir. 1988) (noting that
terms such as “approach each other,” “close to,” “substantially equal,” and “closely
approximate” are ubiquitously used in patent claims and that such usages, when
serving reasonably to describe the claimed subject matter to those of skill in the field of
the invention, and to distinguish the claimed subject matter from the prior art, have been
accepted in patent examination and upheld by the courts) (emphasis added).
33

12

case.”35 The Federal Circuit has also held that the use of the term “about” when
describing a numeric value renders a claim indefinite when the patent “gives no hint as
to which mean value between the [prior art] and the [claimed value] constitutes
infringement.”36
Here, the court disagrees with defendant’s contention that the use of the word
“about” renders these terms invalid due to giving “no hint” as to what weight constitutes
infringement by a potential accused product . The patent compares the weights of the
claimed invention to the prior art: “[t]he assembly is lightweight (9.76-19.53 kg/sq. m or
2-4 pounds/sq. ft.) relative to conventional roofing ballast (48.8-73.2 kg/sq. m or 10-15
pounds/sq. ft.), relying on a combination of weight, edge to edge connection, and
spacer geometry to resist the forces of wind uplift.”37 The specification also describes
as an advantage of the invention “a roofing assembly which weighs roughly one-sixth to
one-third that of conventional ballasted roofs, thus eliminating the need for added
building structural support.”38 Based on the comparative weights of the invention and
the prior art described in the specification, one of skill in the art would be able to
determine the approximate weight of a potential accused product that would, or would
not, be covered by the claims.39 The court adopts plaintiff’s proposed constructions of
35

Pall Corp., 66 F.3d at 1217.
Amgen, Inc. v. Chungai Pharm. Co. Ltd., 927 F.2d 1200, 1218 (Fed. Cir. 1991).
37
‘988 patent, 5:35-40 (emphasis added); see also ‘988 patent, 7:40-44 (“The
spacer geometry serves to reduce to (sic) net forces of wind uplift, thus enabling the
assembly to be lightweight (7.76-19.53 kg/sq. m or 2-4 pounds/sq. ft.) relative to
conventional roofing ballast (48.8-73.2 kg/sq. m or 10-15 pounds/sq. ft).”) (emphasis
added).
38
‘988 patent, 3:30-33 (emphasis added).
39
See, e.g., UCB, Inc. v. KV Pharm. Co. C.A. No. 08-233-JJF, 2009 WL
2524519, at *6 (determining in the facts of that case that “the word ‘about’ should simply
36

13

these terms to mean “distributed weight over the surface area covered by the assembly
of about 2-4 (or 1.67-5) pounds per square foot” and “the distributed weight of the
plurality of PV assemblies over the surface area covered by the assemblies is not more
than about four pounds per square foot.”
5.

means for interlocking
Representative claim 71 of the ‘988 patent recites:
71. The assembly according to claim 55 wherein said photovoltaic
assembly comprises means for interlocking one photovoltaic assembly to
an adjacent photovoltaic assembly.40
Representative claim 72 of the ‘988 patent recites:
72. The assembly according to claim 56 wherein said
photovoltaic/building rooftop assembly comprises means for interlocking
one said photovoltaic assembly to another said photovoltaic assembly.41
The parties agree “means for interlocking” is a means-plus-function term and that

the function specified by “means for interlocking” is “to attach one photovoltaic assembly
to an adjacent photovoltaic assembly.” In light of the parties’ agreement, the court
adopts their proposed function for this term.
Plaintiff’s proposed corresponding structure is “the structures shown in the
figures, including interlocking joints, for example, tongue and groove structures, edge
connection with mechanical clips, intersecting c-channels, adhesives, skewer inserts or
any other structural equivalent manner of interlocking.”
Defendant’s proposed corresponding structure is “photovoltaic assemblies

be construed to mean ‘approximately’”).
40
‘988 patent, claim 71 (emphasis added).
41
‘988 patent, claim 72 (emphasis added).
14

having: interlocking tongue and groove joints along the adjoining lateral edges; edgeto-edge connection via mechanical clips; edge-to-edge connection via c-channels;
edge-to-edge connection via adhesives; or skewer inserts or any structural equivalent
manner of interlocking the lateral edge of one photovoltaic assembly with the lateral
edge of an attached photovoltaic assembly.”
“When looking to the specification for the structure of a § 112 ¶ 6 claim, one must
construe the claim in accordance with all the structures disclosed by the inventor.”42
The parties’ proposed structures each recite the same components for attaching
one photovoltaic assembly to an adjacent photovoltaic assembly.43 Their primary
disagreement on the “means for interlocking” term is whether those components must
attach assemblies edge-to-edge.44
Although, the claims do not recite “edge-to-edge” attachment of one photovoltaic
assembly to an adjacent photovoltaic assembly, the specification provides support for
such requirement. The specification states:
In FIGS. 1C and 1D spacer 132 preferably has a tongue profile 160 along
42

Playtex Prods., Inc. v. Procter & Gamble Co., 400 F.3d 901, 909 (Fed. Cir.
2005); see also Serrano v. Telular Corp., 111 F.3d 1578, 1583 (Fed. Cir. 1997)
(“Disclosed structure [for the purposes of a means-plus-function claim construction]
includes that which is described in a patent specification, including any alternative
structures identified.”).
43
Although plaintiff complains defendant’s proposed structure excludes cchannels, defendant does include c-channels in its proposal. While defendant argues
“the specification of the ‘988 patent actually does not disclose coupling of adjacent
assemblies using c-channels . . . PanelClaw’s proposed construction fairly recognizes
that the ‘988 patent discloses c-channels in this other context and, therefore, a person
of ordinary skill could understand that edge-to-edge connection of adjacent photovoltaic
assemblies using c-channels, mechanical clips, adhesives, etc. is possible.” D.I. 111 at
62.
44
Id. at 54.
15

two edges and a groove profile 162 along its other two edges such that
spacer 132 interlocks with adjacent spacers. In this way, interlocking
joints are formed between adjacent integral assemblies for better
resistance to wind uplift. However, any means of integral locking is
possible.45
The court does not read “any means of integral locking is possible” to mean other that
edge-to-edge interlocking, but rather, to mean edge-to-edge interlocking by means
other than a tongue and groove. This understanding is supported by the disclosure
near the end of the specification that: “[a]s further example, whereas the edge to edge
connection between adjacent modules was often shown as a tongue and groove
assembly, any means of edge connection is possible, including mechanical clips,
adhesives, ‘skewer’ inserts which penetrate the insulation block, and other means.”46
The court also notes that in prior litigation involving the ‘988 patent, a district
court similarly found the disclosed structure for this term required edge connection:
“[t]he structure disclosed in the specification that corresponds to the claimed function is
identified as: ‘modules or spacers with interlocking joints along the adjoining lateral
edges.’”47
The court therefore determines that the corresponding structure for “means for
interlocking” is: “photovoltaic assemblies having: interlocking tongue and groove joints
along the adjoining lateral edges; edge-to-edge connection via mechanical clips; edgeto-edge connection via c-channels; edge-to-edge connection via adhesives; or skewer
inserts or any structural equivalent manner of interlocking the lateral edge of one
45

‘988 patent, 5:14-20 (emphasis added).
‘988 patent, 8:32-37 (emphasis added).
47
SunPower Corp. v. Sunlink Corp., No. CV 08-2807 SBA, 2009 WL 2996724, at
*1 (N.D. Cal. Mar. 16, 2009) (emphasis added).
46

16

photovoltaic assembly with the lateral edge of an attached photovoltaic assembly.”
6.

means for interengaging adjacent photovoltaic assemblies into an array of
photovoltaic assemblies, said array defining a perimeter
Representative claim 36, previously cited in full, contains the specific language

“means for interengaging adjacent photovoltaic assemblies into an array of photovoltaic
assemblies, said array defining a perimeter.”
The parties agree this term is a means-plus-function term.
Plaintiff’s proposed function is “coupling adjacent photovoltaic assemblies into an
array.” Its proposed corresponding structure is “the structures shown in the figures,
including interlocking joints, for example, tongue and groove structures, intersecting cchannels, edge connection with mechanical clips, adhesives, skewer inserts or any
other structural equivalent manner of interengaging.”
Defendant’s proposed function is “to create an interconnected array of PV
assemblies.” Its proposed corresponding structure is “spacers and modules that are
attached to adjacent spacers and modules via a tongue and groove edge-to-edge
connection, or edge-to-edge connection through c-channels, mechanical clips,
adhesives, or skewer inserts.”
As to the function of this term, the court adopts plaintiff’s proposal. The court
agrees with plaintiff that one of ordinary skill in the art would understand that
“interengaging” is synonymous with “coupling.”48 Further, plaintiff’s proposal tracks the
48

Defendant uses the word “coupling” itself in discussing its proposed structure:
“PanelClaw’s proposed construction captures the structures disclosed in the ‘988 patent
for coupling one photovoltaic assembly to an adjacent photovoltaic assembly, and even
includes forms of coupling that are described in other contexts.” D.I. 111 at 62
(emphasis added).
17

claim language that “adjacent photovoltaic assemblies” are “interengaged,” or coupled,
“into an array.” The court determines, therefore, that the function of this term is
“coupling adjacent photovoltaic assemblies into an array.”
As with the “means for interlocking” term, the parties’ proposed structures for
“means for interengaging” each recite the same components for attaching one
photovoltaic assembly to an adjacent photovoltaic assembly. The parties’ primary
dispute over the structure of the “means for interengaging” term is, again, whether there
is a requirement that the assemblies are attached edge-to-edge.
The parties are in apparent agreement that “interlock” and “interengage” are
synonymous. In briefing, plaintiff stated “[o]ne of ordinary skill in the art would
understand that in this context the terms ‘interlock’ and ‘interengage’ are synonymous
and would look to the recited interlocking structures to perform the ‘interengaging’
function.”49 At the Markman hearing, defendant stated:
The word interengaging does not appear in the ‘988 patent. So I don’t
think there’s any disagreement between the parties that the places you
look for interlocking are the places you look for interengaging. I can’t
speak for SunPower, but I don’t see any place where the patent is
distinguishing between interengaging on the one hand and interlocking on
the other.50
The parties’ agree that “interengaging” and “interlocking” are synonymous.
Therefore, the structures disclosed for the interlocking means are the same structures
that may perform the “interengaging” function. Consequently, the court determines
edge-to-edge connection to be required for this term for the reasons discussed with

49
50

Id. at 61.
Markman Tr. at 146:4-12.
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respect to “means for interlocking.” Consequently, court finds the corresponding
structure for “means for interengaging” is “spacers and modules that are attached to
adjacent spacers and modules via a tongue and groove edge-to-edge connection, or
edge-to-edge connection through c-channels, mechanical clips, adhesives, or skewer
inserts.”
7.

means for resisting wind uplift forces sufficiently to eliminate the need for
penetrations to the rooftop
Representative claim 73 of the ‘988 patent recites:
73. The assembly according to claim 1 wherein said assembly further
comprises means for resisting forces of wind uplift sufficiently to eliminate
the need for penetrations of the building rooftop.51
The parties agree this is a means-plus-function term.
Plaintiff’s proposed function is “resisting wind uplift to allow mounting with no

penetrations of the rooftop.” Its proposed corresponding structure is “structures shown
in Figs. 1-4, including a combination of the configuration of the spacers and interlocking
or the use of windspoils, or the equivalents of these structures.”
Defendant argues this term cannot be construed and is invalid pursuant to 35
U.S.C. § 112. Alternatively, defendant’s proposed function is “to resist the force of wind
uplift enough that the assembly does not require roof penetrations.” Its proposed
corresponding structure is “interlocking spacers and/or modules and pavers secured
around the perimeter of the array.”
Defendant’s arguments that this term is indefinite primarily rest on its assertion
that claim 1, from which claim 73 depends, only covers an embodiment having a single
51

‘988 patent, claim 73 (emphasis added).
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spacer and a single module, an assertion the court has rejected. It also contends this
term is indefinite for the same reasons it sets forth in its argument that the Whereby
Clause is indefinite. The court determined that the Whereby Clause is not indefinite and
finds defendant’s arguments equally unpersuasive with regard to this term.
Although in the parties’ briefing each proposed a slightly different function, at the
Markman hearing plaintiff agreed the proposed functions were very similar and it did not
necessarily believe there was much of a difference in the proposals as “it’s sort of two
ways of saying the same thing.”52 Therefore, the court adopts defendant’s proposed
function for this term: “to resist the force of wind uplift enough that the assembly does
not require roof penetrations.”
The court finds that plaintiff’s proposed structure is supported by the figures and
specification. In the Background of the Invention, the specification states “[t]his
invention generally relates to a photovoltaic roofing assembly, and in particular to a
lightweight photovoltaic roofing assembly requiring no roofing penetrations and which
resists wind up-lift due to specialized component geometry and by acting as an integral
assembly.”53 The patent discloses various embodiments performing the recited
function. For instance, describing figures 1A-1D, the patent states “FIGS. 1A to 1D
show views of one embodiment of the invention with spacers resting directly on a
roofing membrane and with spacer geometry designed to minimize wind uplift on the
overall assembly.”54 The specification recites “free air exchange with the spacer

52

Markman Tr. at 163:1-24.
‘988 patent, 1:22-26 (emphasis added).
54
‘988 patent, 3:61-64.
53

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geometry shown has been determined through wind-tunnel testing to aid in the
instantaneous equilibration of air pressures between the top and bottom side of module
106, thus reducing net forces of wind uplift.”55 “The tapered profile 140 [of the spacer]
serves as an aerodynamic wind-block, causing wind which is traveling from the right in
the drawing to flow over the top of module 106, and obstructing its entry to the backside
of module 106.”56 The patent also describes formation of “interlocking joints” “between
adjacent integral assemblies for better resistance to wind uplift”57 and the use of
“windspoils 260, 262, 264, 266, 268 in order to deflect surface winds from entering
below modules 204, 206, 208, 210, 212.”58
The court disagrees with defendant that a corresponding structure must include
perimeter securement. In the prior litigation involving the ‘988 patent, the district court
determined the disclosed structure of this term was “[a] combination of the configuration
of the spacers and interlocking or use of wind spoils.”59 Although somewhat narrower
than the structure plaintiff is suggesting here, that court construed this term and the
structure disclosed in the specification did not include “pavers secured around the
perimeter of the array” as defendant proposes. More importantly, claim 22 of the ‘988
patent, which ultimately depends from claim 1, adds a perimeter securement
requirement: “[t]he assembly of claim 19[, which depends from claim 1,] further
comprising perimeter ties situated around the photovoltaic array and joined with said
55

‘988 patent, 5:2-6.
‘988 patent, 5:10-13.
57
‘988 patent, 5:17-19.
58
‘988 patent, 6:32-34; see also, e.g., ‘988 patent, 6:56-7:9; 7:19-44; 8:32-45.
59
SunPower Corp. v. Sunlink Corp., No. CV 08-2807 SBA, 2009 WL 2996724, at
*2 (N.D. Cal. Mar. 16, 2009) (emphasis added).
56

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photovoltaic array to make an integral array assembly.”60 Because dependent claim 22
adds the requirement of “perimeter ties,” that requirement is not included in claim 1 and
thus, is not required in claim 73, which does not include a perimeter securement
element.
The court determines the structure disclosed in the specification of the ‘988
patent that corresponds to the claimed function is “structures shown in Figs. 1-4,
including a combination of the configuration of the spacers and interlocking or the use of
windspoils, or the equivalents of those structures.”
Order: The Court’s Claim Construction
At Wilmington, this 31st day of August, 2016, having heard oral argument, having
reviewed the papers submitted with the parties’ proposed claim constructions, and
having considered all of the parties’ arguments (whether or not explicitly discussed
herein);
IT IS ORDERED that the disputed claim language in the asserted claims of the
patent-in-suit, as identified by the parties, shall be construed below consistent with the
tenets of claim construction set forth by the United States Court of Appeals for the
Federal Circuit in Phillips v. AWH Corp.,61 as follows:
Claim Term
fluidly coupling

60
61

Construction
allowing a fluid, such as air, to pass
through and around allowing the open
region below a module to connect with
the upper surface of the module

‘988 patent, claim 22 (emphasis added).
415 F.3d 1303 (Fed. Cir. 2005) (en banc).
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Claim Term

Construction

spacer

structure(s) providing support for the
module(s), ensuring consistent spacing
between the modules

variable-height spacer

a spacer that supports the module or
modules at an incline

access openings

openings connecting the upper surface of
the photovoltaic module(s) to the open
region beneath the photovoltaic
module(s)

whereby wind uplift forces are resisted

whereby wind uplift forces are resisted in
excess of the resistance provided by the
weight of the assembly alone

combined weight of about 2-4 (or 1.67-5)
pounds per square foot

distributed weight over the surface area
covered by the assembly of about 2-4 (or
1.67-5) pounds per square foot

plurality of PV assemblies has a weight of
not more than about four pounds per
square foot

the distributed weight of the plurality of
PV assemblies over the surface area
covered by the assemblies is not more
than about four pounds per square foot

means for interlocking

Function: to attach one photovoltaic
assembly to an adjacent photovoltaic
assembly
Structure: photovoltaic assemblies
having: interlocking tongue and groove
joints along the adjoining lateral edges;
edge-to-edge connection via mechanical
clips; edge-to-edge connection via cchannels; edge-to-edge connection via
adhesives; or skewer inserts or any
structural equivalent manner of
interlocking the lateral edge of one
photovoltaic assembly with the lateral
edge of an attached photovoltaic
assembly.

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Claim Term
means for interengaging adjacent
photovoltaic assemblies, said array
defining a perimeter

Construction
Function: coupling adjacent photovoltaic
assemblies into an array
Structure: spacers and modules that are
attached to adjacent spacers and
modules via a tongue and groove edgeto-edge connection, or edge-to-edge
connection through c-channels,
mechanical clips, adhesives, or skewer
inserts

means for resisting wind uplift forces
sufficiently to eliminate the need for
penetrations to the rooftop

Function: to resist the force of wind
uplift enough that the assembly does not
require roof penetrations
Structure: structures shown in Figs. 1-4,
including a combination of the
configuration of the spacers and
interlocking or the use of windspoils, or
the equivalents of those structures
/s/ Mary Pat Thynge
UNITED STATES MAGISTRATE JUDGE

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