Source: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-14-01254/USCOURTS-ca13-14-01254-0/pdf.json

Nature of Suit Code: 830
Nature of Suit: Patent
Cause of Action: 

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United States Court of Appeals 

for the Federal Circuit ______________________ 

EIDOS DISPLAY, LLC, EIDOS III, LLC,

Plaintiffs-Appellants

v.

AU OPTRONICS CORPORATION, AU OPTRONICS 

CORPORATION AMERICA, CHI MEI INNOLUX 

CORPORATION, CHI MEI OPTOELECTRONICS 

USA INC., CHUNGHWA PICTURE TUBES, LTD., 

HANNSTAR DISPLAY CORPORATION,

HANNSPREE NORTH AMERICA, INC.,

Defendants-Appellees

______________________ 

2014-1254

______________________ 

Appeal from the United States District Court for the 

Eastern District of Texas in No. 6:11-cv-00201-LED-JDL, 

Chief Judge Leonard Davis.

______________________ 

Decided: March 10, 2015

______________________ 

ROBERT TYLER GOODWYN, McKenna Long & Aldridge 

LLP, Washington, DC, argued for plaintiffs-appellants. 

Also represented by GASPARE JOSEPH BONO, CASS WALKER 

CHRISTENSON, ROBERT C. NISSEN. 

CHRISTOPHER BENSON, Austin, TX, argued for defendants-appellees. Defendant-appellee Chunghwa Picture 

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2 EIDOS DISPLAY, LLC v. AU OPTRONICS CORPORATION

Tubes, Ltd., also represented by DANIEL LEVENTHAL, PAUL 

ANDREW DYSON, ERIC B. HALL, Norton Rose Fulbright, 

Houston, TX. Defendants-appellees AU Optronics Corporation, AU Optronics Corporation America, also represented by MARVIN CRAIG TYLER, BRIAN A. DIETZEL,

GEOFFREY WILLIAM HEAVEN, Wilson, Sonsini, Goodrich & 

Rosati, PC, Austin, TX. Defendants-appellees Chi Mei 

Innolux Corporation, Chi Mei Optoelectrics, USA Inc., 

Hannspree North America, Inc., Hannstar Display Corporation, also represented by MING-TAO YANG, JACOB ADAM 

SCHROEDER, Finnegan, Henderson, Farabow, Garrett & 

Dunner, LLP, Palo Alto; EDWARD ROBERT YOCHES, Washington, DC. 

______________________ 

Before WALLACH, TARANTO, and CHEN, Circuit Judges.

CHEN, Circuit Judge. 

Plaintiff-Appellants Eidos Display, LLC and Eidos III, 

LLC (Eidos) appeal from the district court’s grant of a 

motion for summary judgment, finding the asserted claim 

of U.S. Patent No. 5,879,958 (the ’958 patent) to be invalid 

as indefinite. Because the claim, when read in light of the 

specification and prosecution history, informed with 

reasonable certainty those skilled in the art at the time 

the patent was filed about the scope of the claimed invention, we reverse the district court’s grant of summary 

judgment of indefiniteness, and remand to the district 

court for further proceedings consistent with our decision.

BACKGROUND

Eidos alleges AU Optronics Corporation, AU Optronics Corporation America, Chi Mei Innolux Corporation, 

Chi Mei Optoelectronics USA Inc., Chunghwa Picture 

Tubes, Ltd., Hannstar Display Corporation, and 

Hannspree North America, Inc. (collectively, “Display 

Manufacturers”) infringe claim 1 of the ’958 patent. The 

’958 patent is directed toward manufacturing processes 

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for an electro-optical device, such as a liquid crystal 

display (LCD). 

The specification of the ’958 patent contains 17 embodiments, each identified by a letter (A through H, J, 

and L through S). Each embodiment describes a manufacturing process that reduces the number of photolithographic steps in creating an LCD panel compared to prior 

art processes, lowering the production cost and improving

yield and production efficiency. ’958 patent, 1:19–3:37 

(describing the prior art as containing seven photolithographic steps), 4:39–14:18 (describing the invention as 

containing four or five photolithographic steps), 14:31–37

(comparing the invention to the prior art). Each embodiment is broken down into a series of “forming” steps that 

deposit material, such as metal, insulator, or passivation 

material, on the substrate or previous layers, as well as a 

series of “photolithographic” steps that etch or remove 

portions of previously-formed material. For example, the 

seventh embodiment, identified by the letter “G,” contains 

five forming steps—G1, G3, G5, G7, and G9—sequentially 

interspersed with five photolithographic steps—G2, G4, 

G6, G8, and G10. Id. at 8:33–67. The specification describes the manufacturing process for each disclosed 

embodiment with reference to the figures. For example, 

figures 54 through 63 depict the process steps of the G 

embodiment. Id. at 18:9–44, 35:31–36:65.

The circuitry in the LCD devices formed by the patented manufacturing processes is the same as circuitry 

formed by a prior art manufacturing process. Id. at 1:16–

18. An example of such a prior art circuit is found in 

figure 169, reproduced below. Id.1 Figure 169 shows a 

matrix with source wiring (S1, S2, S3, . . . Sn) forming the

vertical lines and gate wiring (G1, G2, G3, . . . Gn) form1 Line 16 of column 1 erroneously refers to “FIG. 

169” as “FIG. 165.” 

 

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ing the horizontal lines. Id. at 1:19–23. The source 

wiring is connected to a signal supply circuit to provide 

image data, and the gate wiring is connected to a scanning circuit to provide control signals. Id.; Appellants’ Br. 

at 6–7. 

Important to this appeal, the electrical connection between a source wire and the signal supply circuit is called 

a source wiring connection terminal. The electrical connection between a gate wire and the scanning circuit is 

called a gate wiring connection terminal. In an LCD 

panel, there are many individual source and gate wires, 

each with a connection terminal located at the end of the

wire. Appellants’ Br. at 7 (citing Eidos Display, LLC v. 

AU Optronics Corp., No. 6:11-cv-201 LED-JDL, 2013 WL 

1559729, at *5 (E.D. Tex. Apr. 12, 2013)). During the 

relevant LCD manufacturing process, a non-conductive 

passivation film is formed on top of the wiring and connection terminals. See ’958 patent, 58:34–36 (Step G7). 

The passivation film is then etched away to allow the 

scanning and signal supply circuits to connect to the 

terminals. See id. at 58:37–41 (Step G8). Experts for 

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both parties agree that, at the time of the ’958 patent, the 

only industry practice for this manufacturing process was 

to create individual holes, referred to as “contact holes,” 

through the passivation film to each connection terminal. 

While a single contact hole shared by all the connection 

terminals may have been technically possible, no expert 

was aware of any example or teaching where such a 

contact hole was ever created, and neither party put any 

such teaching into the record, if such a teaching exists.

The asserted claim 1 is the only issued claim in the 

’958 patent and recites:

1. A method for producing an electro-optical device in which an electro-optical material is put between a pair of substrates opposed to each other, 

at least a portion of opposing surfaces of the substrates is insulative, a plurality of source wirings 

and a plurality of gate wirings are formed crossing 

each other on the surface of one of said pair of 

substrates and a transparent pixel electrode and a 

thin film transistor are formed at each of the 

crossing points between the source wirings and 

the gate wirings, wherein the method comprises:

a step G1 of forming a first metal film on the surface of said one substrate,

a first photolithographic step G2 of patterning the 

first metal film to form a gate electrode and a gate 

wiring,

a step G3 of forming a first insulator film, a semiconductor film and an ohmic contact film on the 

surface of said one substrate after the first photolithographic step,

a second photolithographic step G4 of patterning 

the semiconductor active film and the ohmic contact film to form a semiconductor portion above 

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the gate electrode in a state isolated from other 

portions,

a step G5 of forming a second metal film on the 

surface of said one substrate after the second photolithographic step,

a third photolithographic step G6 of patterning 

the second metal film and the ohmic contact film 

to form a source electrode, a drain electrode and a 

channel portion,

a step G7 of forming a passivation film on the surface of said one substrate after the third photolithographic step, and

a fourth photolithographic step G8 of patterning 

the passivation film to form a contact hole reaching the gate wiring, a contact hole reaching the 

drain electrode and a contact hole for source wiring and gate wiring connection terminals, 

a step G9 of forming a transparent conductive film 

on the surface of said one substrate after the 

fourth photolithographic step, and

a fifth photolithographic step G10 of patterning 

the transparent conductive film to form a transparent pixel electrode.

Id. at 58:5–47 (emphasis added to highlight the limitation 

at issue on appeal).

During Markman proceedings in front of the magistrate judge, the primary claim construction dispute focused on the last portion of step G8, “a contact hole for 

source wiring and gate wiring connection terminals.” 

Eidos Display, 2013 WL 1559729, at *4. Eidos argued 

that the disputed limitation requires separate and distinct contact holes for the source wiring connection terminals and gate wiring connection terminals, consistent 

with the standard industry practice and the specification, 

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whereas Display Manufacturers argued that the plain 

language of the disputed limitation requires a shared

contact hole for all connection terminals. Id. The magistrate judge reviewed the claim language, specification, 

and the record in the then-ongoing ex parte reexamination, and determined that the dispute “[wa]s not ripe for 

claim construction, as the dispute [as] presented center[ed] around theories of invalidity pursuant to 

35 U.S.C. § 112.” Id. at *6.

Defendants Chi Mei Innolux Corporation and Chi Mei 

Optoelectronics USA Inc. (collectively, “Innolux”) then 

filed a motion for summary judgment alleging noninfringement, in which they argued for a third construction 

of the disputed limitation, that two different structures be 

formed: 1) a contact hole for source wiring and 2) the gate 

wiring connection terminals, with no corresponding 

contact hole or holes. The district court declined to adopt 

Innolux’s proposed construction, and instead ordered 

briefing as to whether the disputed limitation was definite. Display Manufacturers subsequently filed a motion 

for summary judgment asserting indefiniteness. Eidos, in 

its response to Display Manufacturers’ motion, proposed a 

fourth construction of the disputed limitation: that the 

structure for the limitation could be formed as either a 

single contact hole as Display Manufactures proposed, or 

as separate contact holes as Eidos originally proposed. 

Joint Appendix (J.A.) 33.

The magistrate judge rejected all four proposed constructions of the disputed limitation. Regarding the first, 

second, and fourth proposed constructions, the magistrate 

judge determined that the specification failed to support 

that “a contact hole for source wiring and gate wiring 

connection terminals” could be formed as either separate 

contact holes or a shared contact hole. The magistrate 

judge dismissed Innolux’s proposed construction because 

it required connection terminals to be formed from an 

insulating material, whereas the specification requires 

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the terminals to be made of a conductive material. The 

magistrate judge recommended that the district court 

grant the motion for summary judgment on indefiniteness 

because “the Court is unable to arrive at a construction 

that would allow a person of ordinary skill in the art to 

determine what is claimed when the claim is read in light 

of the specification.” J.A. 34 (citation omitted). The 

district court issued an order adopting the magistrate 

judge’s recommendation and granting the motion for 

summary judgment of indefiniteness. J.A. 22. 

Eidos appealed and we have jurisdiction pursuant to 

28 U.S.C. § 1295(a)(1).

DISCUSSION

A patent must “conclude with one or more claims particularly pointing out and distinctly claiming the subject 

matter which the applicant regards as [the] invention.” 

35 U.S.C. § 112, ¶ 2 (2006).2 Keeping in mind that “patents are not addressed to lawyers, or even to the public 

generally, but rather to those skilled in the relevant art,” 

the patent claims “must be precise enough to afford clear 

notice of what is claimed, thereby appris[ing] the public of 

what is still open to them.” Nautilus, Inc. v. Biosig Instruments, Inc., 134 S. Ct. 2120, 2129 (2014) (internal 

quotation marks omitted). A claim fails to satisfy this 

statutory requirement and is thus invalid for indefiniteness if its language, when read in light of the specification 

and prosecution history, “fail[s] to inform, with reasonable 

2 Paragraph 2 of 35 U.S.C. § 112 was replaced with 

newly designated § 112(b) when § 4(c) of the America 

Invents Act (AIA), Pub. L. No. 112-29, took effect on 

September 16, 2012. Because the applications resulting 

in the patents at issue in this case were filed before that 

date, we will refer to the pre-AIA version of § 112.

 

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certainty, those skilled in the art [at the time the patent 

was filed] about the scope of the invention.” Id. at 2124.3 

We review the grant of summary judgment of indefiniteness de novo, applying the same standard used by the 

district court. Ethicon Endo-Surgery, Inc. v. U.S. Surgical Corp., 149 F.3d 1309, 1315 (Fed. Cir. 1998). We 

review the district court’s ultimate indefiniteness determination de novo. Interval Licensing LLC v. AOL, Inc., 

766 F.3d 1364, 1370 (Fed. Cir. 2014). The indefiniteness 

inquiry here is intertwined with claim construction, see

Atmel Corp. v. Info. Storage Devices, Inc., 198 F.3d 1374, 

1379 (Fed. Cir. 1999), which, because the meaning of the 

claim at issue is clear in view of the intrinsic record and 

undisputed facts, we also review de novo, see Teva Pharm. 

USA, Inc. v. Sandoz, Inc., 135 S. Ct. 831, 840–42 (2015). 

To the extent the district court considered extrinsic evidence in its claim construction order or summary judgment order, that evidence is ultimately immaterial to the 

outcome because the intrinsic record is clear. See Phillips

v. AWH Corp., 415 F.3d 1303, 1318 (Fed. Cir. 2005) (en 

banc) (“[A] court should discount any expert testimony 

that is clearly at odds with the claim construction mandated by the claims themselves, the written description, 

and the prosecution history, in other words, with the 

written record of the patent.” (internal quotation marks 

omitted)). We reverse the district court’s finding of indefiniteness because Eidos’ proposed construction for the 

3 The district court granted summary judgment on 

January 22, 2014, without the benefit of the Supreme 

Court’s guidance in Nautilus. The magistrate judge 

recommended that summary judgment of indefiniteness 

be granted because he determined, under the preNautilus standard, that the asserted claim was “insolubly 

ambiguous.” J.A. 34 (citing Honeywell Int’l v. Int’l Trade 

Comm’n, 341 F.3d 1332, 1338–39 (Fed. Cir. 2003)).

 

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disputed limitation reflects how a person of ordinary skill 

in the art at the time of the invention would have understood the limitation after reading the intrinsic record. See

id. at 1312–18. 

The limitation-at-issue, “a contact hole for source wiring and gate wiring connection terminals,” by itself, might 

suggest to someone unknowledgeable in the field of LCD 

manufacturing that one contact hole is formed for all the 

source wiring connection terminals and gate wiring 

connection terminals, as the Display Manufacturers 

argue. But the limitation, by itself, might also indicate 

that many contact holes are formed for the connection 

terminals. To analogize, a person familiar with cars, 

when reading the sentence “I am going to create an electric car for the United States and United Kingdom,” 

would likely expect different electric cars to be created, 

one set with the steering wheel located on the left for 

driving in the United States, and another set with the 

steering wheel on the right for driving in the United 

Kingdom. The intrinsic record here makes sufficiently 

clear that a person of ordinary skill in the art—someone 

with knowledge of LCD manufacturing—after considering 

the limitation “in the context of the particular claim in 

which the disputed term appears, [and] in the context of 

the entire patent, including the specification,” Phillips, 

415 F.3d at 1313, would understand the limitation-atissue to call for separate, different contact holes for the 

source wiring connection terminals and gate wiring 

connection terminals, rather than one shared contact 

hole.4 

4 During reexamination of the ’958 patent, the examiner concluded that the limitation-at-issue “implicitly 

requires separate contact holes for the source wiring and 

gate wiring connection terminals.” J.A. 6079–80. 

 

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As an initial matter, no party disputes that the state 

of the art for manufacturing LCD panels always had been 

to form contact holes for source wiring connection terminals that are separate from contact holes for gate wiring 

connection terminals. Consistent with that wellestablished practice, the specification teaches that each 

connection terminal for the electro-optical device would 

receive its own contact hole, for two reasons. 

First, nothing in the 172 figures or 58 columns of the 

’958 patent describes how a person of ordinary skill in the 

art would deviate from the known industry practice to 

create a novel shared contact hole for all the connection 

terminals. If the patentee wanted to deviate from the 

standard practice and claim a novel shared contact hole, 

some teaching of how to depart from the common practice 

would not only be expected, but is required. See 35 U.S.C. 

§ 112 (“The specification shall contain a written description of the invention, and the manner and process of 

making and using it, in such full, clear, concise, and exact 

terms as to enable any person skilled in the art . . . to 

make and use the same . . . .”).

Second, the only description corresponding to “a contact hole for source wiring and gate wiring connection 

terminals” in the specification teaches that separate 

contact holes are formed for the different connection 

terminals. This teaching is evident when considering the 

history of the ’958 patent, in particular the patent application to which the ’958 patent claims priority, application number 08/459,925. See Masco Corp. v. United 

States, 303 F.3d 1316, 1324 (Fed. Cir. 2002) (“The prosecution history of a parent application may be considered 

in construing claim terms.” (citing Elkay Mfg. Co. v. Ebco 

Mfg. Co., 192 F.3d 973, 980 (Fed. Cir. 1999) (“When 

multiple patents derive from the same initial application, 

the prosecution history regarding a claim limitation in 

any patent that has issued applies with equal force to 

subsequently issued patents that contain the same claim 

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limitation.”))). The ’925 application originally contained 

seventeen independent claims, J.A. 9419–49, which were 

subject to a seventeen-species restriction, J.A. 9516. The 

specification in the ’925 application, which is substantially the same as the specification in the ’958 patent, contains seventeen embodiments that match with and 

describe the seventeen original independent claims. The 

limitation-at-issue, “a contact hole for source wiring and 

gate wiring connection terminals,” appeared in five of the 

original claims; claim 3 (embodiment B), claim 4 (embodiment C), claim 5 (embodiment D), claim 7 (embodiment 

F), and claim 8 (embodiment G). Original claim 8 ultimately became claim 1 of the patent before us—the ’958 

patent. Although the portion of the specification describing embodiment G does not explain in detail this particular photolithographic step, the portion describing 

embodiment D, which claims this step using identical 

claim language, explicitly describes this photolithographic 

step as forming “a contact hole [] for a source wiring 

connection terminal and a contact hole for a gate wiring 

connection terminal.” ’958 patent, 31:42–53. Both parties 

agree that, as recited in original claim 5 (which corresponds to embodiment D), “a contact hole for source 

wiring and gate wiring connection terminals” requires 

separate contact holes for each connection terminal, 

consistent with Eidos’ proposed construction. Id. at

31:50–53. After reviewing the specification as well as the 

claims originally filed with the Patent Office, we see no 

reason to ascribe a different meaning to the same limitation in original claim 8, i.e., claim 1 of the ’958 patent. 

See Phillips, 415 F.3d at 1314 (“Because claim terms are 

normally used consistently throughout the patent, the 

usage of a term in one claim can often illuminate the 

meaning of the same term in other claims.”).

Even without considering the priority application, the 

specification makes clear that the limitation-at-issue 

requires formation of separate contact holes. Again, with 

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respect to embodiment D, the specification, at one point,

describes “a fourth photolithographic step D8 of patterning the passivation film to remove a portion of the passivation film, . . . forming a contact hole for source wiring 

and gate wiring connection terminals.” ’958 patent, 7:11–

22 (emphasis added). And, as already stated, the specification later clarifies that “photolithographic step D8” 

entails forming “a contact hole [] for a source wiring 

connection terminal and a contact hole for a gate wiring 

connection terminal.” Id. at 31:42–53. The specification 

thus equates the limitation-at-issue with forming separate 

contact holes for the source wiring connection terminal 

and the gate wiring connection terminal. Nothing in the 

specification suggests why the identical phrase recited in 

the claimed “fourth photolithographic step G8” should be 

read differently from the described “fourth photolithographic step D8.” Instead, a person of ordinary skill in 

the art would understand that the phrase, “a contact hole 

for source wiring and gate wiring connection terminals,” 

when used repeatedly throughout the patent, would be

given a consistent meaning. See Energy Transp. Grp., 

Inc. v. William Demant Holding A/S, 697 F.3d 1342, 

1349–50 (Fed. Cir. 2012) (using the description of a word 

in the specification for a different structure to inform the 

meaning of the same word in the claim because “claim 

terms are normally used consistently throughout the 

patent” (quoting Phillips, 415 F.3d at 1314)). 

The limitation-at-issue also appears in original claims 

3, 4, and 7 of the ’925 application, J.A. 9421–25, 9429–30, 

and in the corresponding embodiments B, C, and F of the 

specification, ’958 patent, 5:38–6:8, 6:9–49, 7:64–8:32. 

Display Manufacturers argue that the lack of description

for the limitation-at-issue in embodiments B, C, F, and G, 

as described in the specification, is evidence that the 

structure in those embodiments is different than in embodiment D. We disagree. As set forth above, the relationship between the specification description for 

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embodiment D and original claim 5 establishes the proper 

understanding for the same claim limitation recited in the 

other original claims of the ’925 application, i.e., claim 3 

(embodiment B), claim 4 (embodiment C), claim 7 (embodiment F), and claim 8 (embodiment G). 

The district court dismissed the teachings of the D 

embodiment because structures formed in Step D8, as 

recited in original claim 5 of the ’925 application and in 

the specification, do not precisely mirror the structures 

formed in the claimed Step G8. J.A. 29. The magistrate 

judge noted that, in addition to the “contact hole for 

source wiring and gate wiring connection terminals,” Step 

G8 forms a contact hole reaching the gate wiring and a 

contact hole reaching the drain electrode, whereas, in the 

D embodiment, the contact hole reaching the gate wiring 

is formed during Step D4, and a contact hole reaching the 

drain electrode is not mentioned. J.A. 29–30. Relatedly, 

Display Manufacturers argue that the different embodiments have a different number of steps and have a different sequence in which the patterns are etched, which they 

argue results in “a fundamentally different approach to 

manufacturing a [device].” Appellees’ Br. at 8–9. Different embodiments, however, are expected to have differences, and neither the magistrate judge nor Display 

Manufacturers explain how the noted differences in the 

structures of the embodiments impact the structure of the 

limitation-at-issue or impact how a person of ordinary 

skill in the art would have understood the limitation. 

Instead, the embodiments all similarly describe manufacturing processes for an electro-optical device using a 

reduced number of photolithographic steps over the prior 

art, and the structure for the limitation-at-issue is formed 

in the same context in each embodiment—in a “photolithographic step [] of patterning the passivation film.” ’958 

patent, 6:4–5, 6:43–44, 7:11–12, 8:23–24, 8:57–58. This 

similar context of the limitation-at-issue, in similar

embodiments, supports the conclusion that a person of 

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ordinary skill in the art would adopt the same understanding for the same limitation recited in claim 1 of the 

’958 patent. 

Finally, Display Manufacturers argue that permitting 

separate contact holes to be covered by the limitation “a 

contact hole for source wiring and gate wiring connection 

terminals” would require rewriting the limitation, which 

is impermissible except in certain situations. Appellees’ 

Br. at 29 (citing Source Vagabond Sys., Ltd. v. Hydrapak, 

Inc., 753 F.3d 1291, 1301 (Fed. Cir. 2014)). Determining

how a person of ordinary skill in the art would understand the limitation, however, is different from rewriting

the limitation. Here, because a person of ordinary skill in 

the art would understand that the limitation “a contact 

hole for source wiring and gate wiring connection terminals” means separate contact holes for source wiring 

connection terminals and gate wiring connection terminals, adopting such a construction is not rewriting the 

claim limitation.

* * *

The ’958 patent teaches a person of ordinary skill in 

the art that “a contact hole for source wiring and gate 

wiring connection terminals” is formed by etching separate contact holes for the source wiring connection terminals and for the gate wiring connection terminals, as 

described in the specification and prosecution history. 

Therefore, the limitation “a contact hole for source wiring 

and gate wiring connection terminals” in claim 1 of the 

’958 patent is not indefinite under 35 U.S.C. § 112, ¶ 2. 

We reverse the judgment of indefiniteness and remand to 

the district court for further proceedings consistent with 

this opinion.

REVERSED AND REMANDED

COSTS

Each party shall bear its own costs. 

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