United States Court of Appeals 

for the Federal Circuit ______________________ 

LIGHTING BALLAST CONTROL LLC,

Plaintiff-Appellee

v.

PHILIPS ELECTRONICS NORTH AMERICA 

CORPORATION,

Defendant

UNIVERSAL LIGHTING TECHNOLOGIES, INC.,

Defendant-Appellant

______________________ 

2012-1014

______________________ 

Appeal from the United States District Court for the 

Northern District of Texas in No. 09-CV-0029, Judge Reed 

O’Connor.

______________________ 

Decided: June 23, 2015 

______________________ 

JONATHAN TAD SUDER, Friedman, Suder & Cooke, 

Fort Worth, TX, for plaintiff-appellee. Also represented by

DAVID ARTHUR SKEELS; ROBERT GREENSPOON, Flachsbart 

& Greenspoon, LLC, Chicago, IL; ANDREW JOHN DHUEY, 

Berkeley, CA. 

STEVEN J. ROUTH, Orrick, Herrington & Sutcliffe LLP, 

Washington, DC, for defendant-appellant. Also represent-
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

2

ed by STEN JENSEN, T. VANN PEARCE, JR., DIANA M. SZEGO;

JOHN R. INGE, Tokyo, Japan. 

LEONARD AGNETA, University of Maine School of Law, 

Portland, ME, for amicus curiae University of Maine 

School of Law, dba Maine Patent Program. 

GEORGE C. SUMMERFIELD, JR., Stadheim & Grear, 

Ltd., Chicago, IL, for amici curiae Wisconsin Alumni 

Research Foundation, Nutech Ventures, Inc., STC.UNM, 

Unemed Corporation, Telecommunications Research 

Laboratories, dba TR Tech, Rensselaer Polytechnic Institute, Tec Edmonton, The Public Patent Foundation. Also 

represented by ROLF STADHEIM. 

MAXIM H. WALDBAUM, Eaton & Van Winkle LLP, New 

York, NY, for amicus curiae Federation Internationale 

Des Conseils En Propriete Industrielle. Also represented 

by ROBERT KATZ, Katz PLLC, Dallas, TX. 

ANDY IVAN NIRANJAN COREA, St. Onge Steward Johnston & Reens, LLC, Stamford, CT, for amicus curiae 

Connecticut Intellectual Property Law Association. Also 

represented by STEPHEN PATRICK MCNAMARA, TODD M.

OBERDICK.

WILLIAM LARRY RESPESS, Sheppard, Mullin, Richter & 

Hampton LLP, San Diego, CA, for amicus curiae The San 

Diego Intellectual Property Law Association. 

JOSEPH R. RE, Knobbe, Martens, Olson & Bear, LLP, 

Irvine, CA, for amicus curiae Federal Circuit Bar Association. Also represented by SHEILA N. SWAROOP; JOSEPH M.

REISMAN, San Deigo, CA; TERENCE PATRICK STEWART,

Stewart & Stewart, Washington, DC.
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

3

JANET BETH LINN, Eckert Seamans Cherin & Mellott, 

LLC, White Plains, NY, for amicus curiae The Association 

of the Bar of the City of New York. 

CHARLES W. SHIFLEY, Banner & Witcoff, Ltd., Chicago, IL, for amicus curiae Intellectual Property Law Association of Chicago. 

JOHN W. SHAW, Shaw Keller LLP, Wilmington, DE, 

for amicus curiae Delaware Chapter of the Federal Bar 

Association. Also represented by KAREN E. KELLER.

 

CHARLES HIEKEN, Fish & Richardson, P.C., Boston, 

MA, for amicus curiae Paul R. Michel. Also represented 

by JOHN A. DRAGSETH, Minneapolis, MN. 

CHIDAMBARAM SUBRAMANIAN IYER, Sughrue Mion, 

PLLC, Washington, DC, for amicus curiae Sigram 

Schindler Beteiligungsgesellschaft MBH. 

JENNIFER KUHN, Law Office of Jennifer Kuhn, Austin, 

TX, for amicus curiae Austin Intellectual Property Law 

Association. Also represented by ADEN M. ALLEN, Wilson, 

Sonsini, Goodrich & Rosati, PC, Austin, TX. 

HARRY C. MARCUS, Locke Lord, LLP, New York, NY, 

for amicus curiae American Intellectual Property Law 

Association. Also represented by ROBERT K. GOETHALS;

JOSEPH ANTHONY FARCO, Locke Lord, Bissell & Liddell, 

LLP, New York, NY; JEFFREY I.D. LEWIS, Fried, Frank, 

Harris, Shriver & Jacobson LLP, New York, NY. 

LAUREL G. BELLOWS, Bellows and Bellows, P.C., Chicago, IL, for amicus curiae American Bar Association. 

Also represented by ROBERT FRANCIS ALTHERR, JR., PAUL 

MICHAEL RIVARD, Banner & Witcoff, Ltd., Washington, 

DC. 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

4

JOHN D. VANDENBERG, Klarquist Sparkman, LLP, 

Portland, OR, for amicus curiae Microsoft Corporation. 

Also represented by ANDREW M. MASON.

THOMAS G. HUNGAR, Gibson, Dunn & Crutcher LLP, 

Washington, DC, for amici curiae Cisco Systems, Inc., 

Dell Inc., EMC Corporation, Intel Corporation, SAP 

America, Inc., SAS Institute Inc. Also represented by

MATTHEW D. MCGILL; ALEXANDER N. HARRIS, San Francisco, CA. 

R. CARL MOY, William Mitchell College of Law, St. 

Paul, MN, for amicus curiae Intellectual Property Institute of the William Mitchell College of Law. 

DARYL JOSEFFER, King & Spalding LLP, Washington, 

DC, for amici curiae Google Inc., Amazon.com, Inc., 

Hewlett-Packard Company, Red Hat, Inc., Yahoo! Inc. 

Also represented by ADAM CONRAD, Charlotte, NC. 

NATHAN K. KELLEY, Office of the Solicitor, United 

States Patent and Trademark Office, Alexandria, VA, for 

amicus curiae United States. Also represented by ROBERT 

J. MCMANUS, KRISTI L. R. SAWERT; MARK R. FREEMAN,

SCOTT R. MCINTOSH, Appellate Staff, Civil Division, 

United States Department of Justice, Washington, DC. 

PAUL H. BERGHOFF, McDonnell, Boehnen, Hulbert & 

Berghoff, LLP, Chicago, IL, for amicus curiae Intellectual 

Property Owners Association. Also represented by 

CHRISTOPHER D. BUTTS; RICHARD F. PHILLIPS, ExxonMobil 

Chemical Company, Houston, TX; KEVIN H. RHODES, 3M 

Innovative Properties Company, St. Paul, MN; HERBERT 

CLARE WAMSLEY, JR., Intellectual Property Owners Association, Washington, DC. 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

5

ROGER LEE COOK, Kilpatrick Townsend & Stockton 

LLP, San Francisco, CA, for amicus curiae Ad Hoc Committee of Patent Owners. 

PETER S. MENELL, University of California Berkeley 

School of Law, Berkeley, CA, for amicus curiae Peter S. 

Menell. 

______________________ 

Before LOURIE, O’MALLEY, and REYNA, Circuit Judges.1

REYNA, CIRCUIT JUDGE. 

This case returns to us on remand from the Supreme 

Court of the United States and was returned to the panel 

for reconsideration in light of Teva Pharmaceuticals USA, 

Inc. v. Sandoz, Inc., 574 U.S. ___, 135 S. Ct. 831 (2015). 

Appellant Universal Lighting Technologies, Inc. (“ULT”) 

appeals four issues. We affirm. 

I 

A. BACKGROUND OF THE TECHNOLOGY

High levels of current are required to cause a fluorescent lamp to emit visible light. As the panel explained in 

the initial panel opinion in this case, Lighting Ballast 

Control LLC v. Philips Elecs. N. Am. Corp. (“Lighting 

Ballast I”), 498 Fed. App’x 986 (Fed. Cir. 2013), fluorescent lamp fixtures typically include an electronic ballast 

to regulate electric current flow. An electronic ballast is a 

device that maintains current levels high enough to start 

the lamp but that prevents current from reaching destructive levels. When a lamp is removed from its holders 

or when a filament is broken, current provided by the 

1 Pursuant to Fed. Cir. Internal Operating Procedure 15 ¶ 2(b)(ii), Circuit Judge Lourie was designated to 

replace Randall R. Rader, now retired, on this panel.

 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

6

ballast suddenly ceases to flow through the lamp and 

dissipates back into the ballast circuitry. The dissipated 

current can destroy the ballast and create an electric 

shock hazard for someone servicing the lamp.

U.S. Patent No. 5,436,529 (“the ’529 patent”), assigned to Lighting Ballast LLC (“Lighting Ballast”), 

discloses an electronic ballast with the ability to shield 

itself from destructive levels of current when a lamp is 

removed or becomes defective. ’529 patent col. 2 ll. 39-47. 

Claim 1 recites:

1. An energy conversion device employing an oscillating resonant converter producing oscillations, having DC input terminals producing a 

control signal and adapted to power at least 

one gas discharge lamp having heatable filaments, the device comprising:

voltage source means providing a constant or variable magnitude DC voltage between the DC 

input terminals;

output terminals connected to the filaments of the 

gas discharge lamp;

control means capable of receiving control signals 

from the DC input terminals and from the resonant converter, and operable to effectively initiate the oscillations, and to effectively stop the 

oscillations of the converter; and direct current 

blocking means coupled to the output terminals and operable to stop flow of the control 

signal from the DC input terminals, whenever 

at least one gas discharge lamp is removed 

from the output terminals or is defective.

’529 patent col. 11 ll. 49-68 (emphasis added to relevant 

terms).
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

7

B. PROCEDURAL HISTORY

On February 24, 2009, Lighting Ballast filed suit 

against ULT asserting infringement of the ’529 patent. 

The parties engaged in claim construction briefing and 

the court held a hearing thereon. ULT argued that the 

term “voltage source means” is governed by 35 U.S.C. 

§ 112 ¶ 6 and that the claims are invalid under 35 U.S.C. 

§ 112 ¶ 2 as indefinite because the specification fails to 

disclose what structure corresponded to the “voltage 

source means” limitation. The district court initially 

agreed with ULT.

Lighting Ballast filed a motion for reconsideration. 

The district court reversed course, finding that its initial 

construction of “voltage source means” was incorrect. The 

district court noted that its prior ruling “unduly discounted the unchallenged expert testimony” and “exalted form 

over substance and disregarded the knowledge of a person 

of ordinary skill in the art.” Lighting Ballast Control, 

LLC v. Philips Elecs. N. Am. Corp., No. 7:09-CV-29, 2010 

WL 4946343, at *12 (N.D. Tex. Dec. 2, 2010). The district 

court cited testimony from an expert for Lighting Ballast, 

Dr. Victor Roberts, and the inventor, Andrzej Bobel, both 

of whom testified that one of skill in the art would understand the claimed “voltage source means” to correspond to 

a rectifier, which converts alternating current (“AC”) to 

direct current (“DC”), or other structure capable of supplying useable voltage to the device. Thus, the district court 

concluded that the term “voltage source means” had 

sufficient structure to avoid the strictures of § 112 ¶ 6 and 

denied ULT’s motion.

Thereafter, ULT renewed its argument that the asserted claims are invalid as indefinite, this time couched 

as a motion for summary judgment. J.A. 62. The district 

court noted that “ULT presents no additional basis for 

holding the asserted claims invalid.” Id. The district 

court, thus, declined to revisit the issue for a third time 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

8

and adopted its prior findings and analysis regarding the 

definiteness of the asserted claims. Id.

Starting on June 13, 2011, the district court held a jury trial on the issue of whether ULT’s accused lighting 

ballast products infringe claims 1, 2, and 5 of the ’529 

patent. The jury returned a verdict finding the ’529 

patent valid and infringed and awarded $3 million in 

damages to Lighting Ballast.

ULT moved for judgment as a matter of law (“JMOL”) 

on three grounds, as relevant to this appeal: 1) the record 

does not contain legally sufficient evidence that the 

accused ULT products meet the “direct current blocking 

means” limitation of claim 1 of the ’529 patent; 2) the 

record does not contain legally sufficient evidence that the 

accused ULT products meet the “connected to” limitation 

of claim 1 of the ’529 patent; 3) the record does not contain legally sufficient evidence that the accused products 

meet the “control means” limitation. The district court 

denied the relevant portions of ULT’s JMOL. ULT appealed. 

After an initial panel decision reversing the judgment 

of the district court regarding indefiniteness of the asserted claims based on the “voltage source means” limitation, 

Lighting Ballast I, this court granted Lighting Ballast’s

petition for rehearing en banc, Lighting Ballast Control 

LLC v. Philips Elecs. N. Am. Corp., 500 Fed. App’x 951 

(Fed. Cir. 2013), in order to reconsider the holding in 

Cybor Corp. v. FAS Technologies, Inc., 138 F.3d 1448 

(Fed. Cir. 1998) (en banc), establishing the standard of 

appellate review of district court claim construction 

decisions. The case was heard en banc on September 13, 

2013. The court issued an opinion affirming that claim 

construction is an issue of law that this court reviews de 

novo. Lighting Ballast Control LLC v. Philips Elecs. N. 

Am. Corp. (“Lighting Ballast II”), 744 F.3d 1272 (Fed. Cir. 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

9

2014) (en banc). Lighting Ballast filed a petition for a 

writ of certiorari with the Supreme Court.

Before the Supreme Court acted on the petition, it issued an opinion in Teva Pharmaceuticals USA, Inc. v. 

Sandoz, Inc., 574 U.S. ___, 135 S. Ct. 831 (2015). In that 

case, the Supreme Court reversed a decision from this 

court, holding that while the ultimate question of the 

proper construction of a claim is a legal question that this 

court reviews de novo, there may be underlying “subsidiary” factual findings by the district court related to the 

extrinsic record that are reviewed for clear error. The 

Supreme Court held that this conclusion flows from Rule 

52 of the Federal Rules of Civil Procedure and the Supreme Court’s prior opinions, such as Markman v. 

Westview Instruments, Inc., 517 U.S. 370 (1996). 

Thereafter the Supreme Court granted Lighting Ballast’s petition for a writ of certiorari, vacated the en banc 

opinion, and remanded it to this court for further consideration in light of Teva. 

II

A. “VOLTAGE SOURCE MEANS” 

As noted above, the district court initially construed 

the “voltage source means” limitation in claim 1 of the 

’529 patent as a means-plus-function limitation. Based on 

this conclusion, the court looked for a disclosed structure 

in the specification to correspond to the voltage source 

function, but found none. These combined conclusions 

rendered the patent invalid as indefinite. After Lighting 

Ballast filed a motion for reconsideration, the district 

court reversed course, finding that its initial construction 

of “voltage source means” was incorrect. The district 

court noted that its prior ruling “unduly discounted the 

unchallenged expert testimony” and “exalted form over 

substance and disregarded the knowledge of a person of 

ordinary skill in the art.” Lighting Ballast Control, LLC 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

10

v. Philips Elecs. N. Am. Corp., No. 7:09-cv-29, 2010 WL 

4946343, at *10, *12 (N.D. Tex. Dec. 2, 2010). The district 

court cited testimony from an expert for Lighting Ballast, 

Dr. Victor Roberts, and the inventor, Andrzej Bobel, both 

of whom testified that one of skill in the art would understand the claimed “voltage source means” to correspond to

a rectifier, which converts alternating current (“AC”) to 

direct current (“DC”), or other structure capable of supplying useable voltage to the device. Thus, the district court 

concluded that the term “voltage source means” had 

sufficient structure to avoid the strictures of § 112 ¶ 6. 

The district court reconfirmed this finding when it denied 

ULT’s motion for summary judgment of invalidity, expressly stating it would not consider the question again.

ULT argues that the district court erred when it held 

that the term “voltage source means” is not governed by 

§ 112 ¶ 6, both in response to Lighting Ballast’s motion 

for reconsideration and in response to ULT’s later motion 

for summary judgment. ULT contends that the extrinsic 

evidence presented by Lighting Ballast and accepted by 

the district court cannot overcome the presumption that 

the term is in means-plus-function format for two reasons. 

First, ULT believes that Lighting Ballast failed to identify 

intrinsic evidence showing that a person of ordinary skill 

in the art would understand “voltage source means” to be 

structural. Second, ULT contends that, at best, “voltage 

source means” refers to any structure capable of performing that function rather than the definite structure of a 

rectifier, as employed in ULT’s products. ULT contends 

that, because the written description of the specification 

fails to disclose structure corresponding to the claimed 

function of the “voltage source means” and the extrinsic 

evidence offered did not adequately identify a single 

structure, the asserted claims are invalid. 

Citing Rule 51 of the Federal Rules of Civil Procedure, 

Lighting Ballast argues that ULT waived any argument 

regarding the proper construction of “voltage source 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

11

means” by failing to raise the issue in either its pre- or 

post-verdict motions for judgment as a matter of law. 

Lighting Ballast also argues that Ortiz v. Jordan, 562 

U.S. 180 (2011), prevents ULT from appealing the denial 

of ULT’s summary judgment motion regarding indefiniteness because Ortiz forbids a party from appealing from an 

order denying summary judgment after a full trial on the 

merits. In the alternative, Lighting Ballast argues that 

the district court’s construction was correct because this 

court’s precedent allows “use of even purely functional 

claim language to show that the limitation as a whole 

suggests structure.” Appellee’s Resp. Br. at 40. Lighting 

Ballast contends that a person of ordinary skill in the art 

would immediately recognize the implicit disclosure of a 

rectifier in the “voltage source means” limitation. Lighting Ballast concludes that ULT cannot show clear error in 

the district court’s consideration of the extrinsic evidence 

in reaching the conclusion that ULT failed to meet its 

burden to prove the ’529 patent invalid as indefinite.

As a preliminary matter, we reject Lighting Ballast’s 

argument that ULT waived its argument regarding 

“voltage source means” because ULT was not required to 

object to claim construction under Rule 51 after ULT 

made its claim construction position clear to the court and 

the court rejected it. We disagree that Ortiz v. Jordan

controls here. Ortiz addressed a circumstance in which a 

trial court denied summary judgment on grounds that 

material issues of fact prevented judgment as a matter of 

law. In those circumstances, the defendant remained 

obliged to present its argument to the trier of fact and 

failure to do so prevented raising it on appeal. While the 

third and final time the district court addressed the issue 

of indefiniteness based on the term “voltage source 

means” was in the context of summary judgment, the 

issue of whether a claim term is governed by § 112 ¶ 6 is a 

claim construction issue. Personalized Media Commc’n, 

LLC v. Int’l Trade Comm’n, 161 F.3d 696, 702 (Fed. Cir. 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

12

1998) (“[w]hether certain claim language invokes 35 

U.S.C. § 112, ¶ 6 is an exercise in claim construction”); see 

also Robert Bosch, LLC v. Snap-On Inc., 769 F.3d 1094, 

1098 (Fed. Cir. 2014) (“[d]etermining whether certain 

claim language invokes § 112, ¶ 6 is an exercise in claim 

construction”) (internal quotations omitted). And claim 

construction is an issue for the court, not the jury. 

Markman v. Westview Instruments, Inc., 517 U.S. 370, 

391 (1996). When the district court denied ULT’s motion 

for summary judgment, it did not conclude that issues of 

fact precluded judgment; it effectively entered judgment 

of validity to Lighting Ballast.

We conclude that ULT did not waive its argument 

that the asserted claims are invalid for indefiniteness. It 

is generally accepted that a district court’s claim construction order is within the class of decisions that do not 

terminate litigation and yet may be appealed upon resolution of the case and issuance of a final judgment. See, e.g.,

O2 Micro Int’l Ltd. v. Beyond Innovation Tech. Co., 521 

F.3d 1351, 1359 (Fed. Cir. 2008) (holding that under Fifth 

Circuit law the appellants’ arguments on appeal regarding claim construction were not waived even though 

appellants did not object to the jury instructions because 

the arguments were made clear to the district court and 

the district court did not clearly indicate that it was open 

to changing its claim construction) (citation omitted); Creo 

Prod., Inc. v. Presstek, Inc., 305 F.3d 1337, 1346 (Fed. Cir. 

2002) (finding that party preserved its indefiniteness 

argument regarding the application of § 112 ¶ 6 for appeal 

because the district court resolved the issue prior to 

appeal). As ULT points out in its brief, ULT argued 

before the district court that the asserted claims were 

indefinite under § 112 ¶ 2 because the term “voltage 

source means” was governed by § 112 ¶ 6 and lacked 

corresponding structure in the written description. The 

district court addressed this issue during claim construction proceedings. The district court initially accepted 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

13

ULT’s position, J.A. 804-15, reversed itself thereafter, 

id. at 16-24, and declined to resolve the issue a third time 

when ULT moved for summary judgment on this issue, 

id. at 62. This is sufficient to preserve the issue for 

appeal. 

Rule 51 does not change this result where a party’s 

position on claim construction is made clear before the 

district court and the district court has rejected that 

position. See Taita Chem. Co., Ltd. v. Westlake Styrene, 

LP, 351 F.3d 663, 667-68 (5th Cir. 2003) (stating that a 

party may be excused from objecting to a jury charge 

under Rule 51 of the Federal Rules of Civil Procedure

where the party’s position is clear from the record and the 

district court made clear that a further objection would be 

unavailing, such as where a party previously filed objections and the district court made clear no more objections 

would be heard); Lang v. Texas & P. Ry. Co., 624 F.2d 

1275, 1279 (5th Cir. 1980) (“[Rule 51 of the Federal Rules 

of Civil Procedure] is not without exceptions, [ ] and the 

failure to object [to the jury charge] may be disregarded if 

the party’s position has previously been made clear to the 

court and it is plain that a further objection would have 

been unavailing.”); see also Cardiac Pacemakers, Inc. v. 

St. Jude Medical, Inc., 381 F.3d 1371, 1381 (Fed. Cir. 

2004) (“When the claim construction is resolved pre-trial, 

and the patentee presented the same position in the 

Markman proceeding as is now pressed, a further objection to the district court’s pre-trial ruling may indeed 

have been not only futile but unnecessary. . . . Objection 

under Rule 51 [of the Federal Rules of Civil Procedure] 

was not required to preserve the right to appeal the 

Markman ruling.”) (under Seventh Circuit law). ULT was 

not required to object to the jury instructions to preserve 

this issue for appeal because it made clear to the district 

court its position on the issue and the issue was finally 

resolved by the district court prior to trial. 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

14

Having addressed the preliminary issue of waiver, we 

now move to the merits. The district court made findings 

of fact based on extrinsic evidence. See Teva, 574 U.S. at

___, 135 S. Ct. at 842. Under the circumstances, it was 

not legal error for the district court to rely on extrinsic 

evidence, because the extrinsic evidence was “not used to 

contradict claim meaning that is unambiguous in light of 

the intrinsic evidence.” Phillips v. AWH Corp., 415 F.3d 

1303, 1324 (Fed. Cir. 2005). For example, the district 

court determined that “while the ‘voltage source means’ 

term does not denote a specific structure, it is nevertheless understood by persons of skill in the lighting ballast 

design art to connote a class of structures, namely a 

rectifier, or structure to rectify the AC power line into a 

DC voltage for the DC input terminals.” J.A. 22. The 

district court went on to note that the language following 

“voltage source means” in the claim—“providing a constant or variable magnitude DC voltage between the DC 

input terminals”—“when read by one familiar with the 

use and function of a lighting ballast, such as the one 

disclosed by the 529 Patent, [sic] would understand a 

rectifier is, at least in common uses, the only structure 

that would provide ‘a constant or variable magnitude DC 

voltage’”. Id. at 23. The district court further noted that 

“[i]t is clear to one skilled in the art that to provide a DC 

voltage when the source is a power line, which provides 

an AC voltage, a structure to rectify the line is required 

and is clear from the language of the ‘voltage source 

means’ term.” Id. We defer to these factual findings, 

absent a showing that they are clearly erroneous. 

The district court’s factual findings are supported by 

the record. Specifically, these factual findings are supported by the testimony of Dr. Roberts and Mr. Bobel. 

Mr. Bobel testified in his deposition that the “voltage 

source means” limitation connotes a rectifier to one 

skilled in the art. Mr. Bobel further explained that a 

battery could likewise provide the necessary DC supply 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

15

voltage described in the patent. Similarly, Dr. Roberts 

explained that the “voltage source means” limitation 

suggests to him a sufficient structure, or class of structures, namely a rectifier if converting AC from a “power 

line source” to DC for a “DC supply voltage” or a battery if 

providing the DC supply voltage directly to the DC input 

terminals. This expert testimony supports a conclusion 

that the limitations convey a defined structure to one of 

ordinary skill in the art. See Rembrandt Data Techs., LP 

v. AOL, LLC, 641 F.3d 1331, 1341 (Fed. Cir. 2011). 

Because the district court’s factual findings demonstrate 

that the claims convey sufficient structure, the district 

court was correct to conclude that the term “voltage 

source means” is not governed by § 112 ¶ 6. As such, we 

affirm the district court’s decision concerning “voltage 

source means.”

B. “DIRECT CURRENT BLOCKING MEANS” 

The district court initially construed the term “direct 

current blocking means” to be governed by § 112 ¶ 6. The 

district court then determined that a capacitor or diode 

was the disclosed corresponding structure. The district 

court later amended this construction to indicate that this 

term requires that each set of output terminals be connected to a DC blocking capacitor. J.A. 58. 

ULT argues that the district court erred when it 

modified its construction of the “direct current blocking 

means” term by improperly adding a requirement that 

each set of output terminals be connected to a DC blocking capacitor. ULT argues that without this limitation on 

the claim, it is clear that the asserted claims are anticipated by two prior art references: JP 1-157099 (“JP ’099”)

and JP 61-153997 (“JP ’997”). 

Lighting Ballast counters that ULT failed to preserve 

any issues related to JP ’099 for appeal by not raising 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

16

JP ’099 before the jury. Lighting Ballast also contends

that ULT’s arguments fail on the merits.2

As noted above, where the issue raised in a motion for 

summary judgment is a pure question of law or, as in the 

case of claim construction, an issue for the court to decide,

the denial of a party’s motion for summary judgment 

generally results in a reciprocal grant of summary judgment to the other party. For issues of fact like anticipation, on the other hand, the denial of a motion for 

summary judgment usually only indicates that there are 

questions of fact to be resolved. In this case, the parties 

treated the district court’s denial of ULT’s motion for 

summary judgment of invalidity as though it was a grant 

of a motion for summary judgment of no anticipation 

based on JP ’099, see J.A. 5234, even though no such 

motion was ever filed. Anticipation is a question of fact 

that is ultimately for the jury to decide. While ULT 

argues it could not have prevailed on its anticipation 

defense if operating under the district court’s amended 

claim construction, we have no factual record upon which 

to assess that argument. We conclude that, absent a 

stipulation between the parties regarding anticipation, 

ULT had to present the question to the jury in order to 

preserve its right to raise it before us.

We turn to the issue of anticipation by JP ’997. The 

district court construed “direct current blocking means” as 

requiring a capacitor or diode at every output terminal. 

Because JP ’997 does not disclose a capacitor or diode at 

every output terminal, the district court concluded that a 

2 Lighting Ballast also makes a summary argument 

without citation that ULT waived any arguments regarding dependent claims 2 and 5 by failing to appeal the 

judgment of validity of these claims. We decline to address this arguments given the insufficient explanation 

and lack of legal basis supporting the argument. 

 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

17

material fact existed as to whether JP ’997 anticipates the

claims. The parties disputed the issue at trial, and the 

jury returned a verdict of no anticipation. 

The parties agree that the term “direct current blocking means” is governed by § 112 ¶ 6. The parties also 

agree that the corresponding structure is a collection of 

capacitors or diodes. The only point of disagreement is 

whether the structure requires a capacitor/diode coupled 

to every set of output terminals or only those through 

which the DC control signal passes and whether, under 

the correct construction, JP ’997 anticipates the asserted 

claims. 

ULT has failed to show reversible error in the district 

court’s construction of the term “direct current blocking 

means.” Claim 1 recites “output terminals” and a “direct 

current blocking means coupled to the output terminals . . . .” The plain language of the claims requires a 

direct current blocking means at every output terminal. 

Under the district court’s construction, the jury’s verdict 

is supported by substantial evidence. At trial, Dr. Zane 

testified that JP ’997 does not teach a DC blocking means 

attached to each of the output terminals. J.A. 13340-41. 

Dr. Giesselmann failed to offer any testimony regarding 

structural equivalency. As such, we hold that the district 

court’s construction of “direct current blocking means” 

was not erroneous, and that the jury’s verdict of no anticipation is supported by substantial evidence.

C. “WHENEVER . . . DEFECTIVE” 

We turn to the construction of “whenever at least one 

discharge lamp is removed from the output terminals or is

defective.” The “direct current blocking means” recited in 

claim 1 is “operable to stop flow of the control signal from 

the DC input terminals, whenever at least one gas dis-
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

18

charge lamp . . . is defective.”3 The district court construed “defective” to mean “whenever the direct current 

path between [two terminals] is broken.” A51. The court 

relied on the following language in the specification for 

support: “the [direct current blocking means] will be held 

discharged for any period of time as long as: (i) there is an 

unbroken direct current path DCP between terminal B+ 

and terminal CTa . . . .” 

The district court’s construction is supported by the 

intrinsic record. The DC blocking means does not block 

control signal when a lamp is inserted into its holders and 

has a working filament. There is no need to block current 

in this instance because the circuit is closed, and there is 

no danger that current will dissipate into the ballast 

circuitry. As the district court recognized, on the other 

hand, the DC blocking means blocks control signal when a 

lamp is removed or when the lamp has a broken filament, 

i.e., when the direct current path between the relevant 

terminals (terminals B+ and CTa) is broken. As a result, 

the district court’s claim construction was not erroneous. 

D. “CONNECTED TO” 

Before trial, the parties did not propose that the district court construe the term “connected to.” ULT did not 

ask for its proposed construction until after trial. In 

resolving ULT’s motion for JMOL, the district court 

construed the term to mean the same thing as “for connection to.”

ULT argues that its accused products do not include 

“output terminals connected to the filaments” of a lamp as 

required by claims 1, 2, and 5 because the term means 

something different from “for connection to.” Lighting 

3 Lighting Ballast argues that ULT waived “whenever . . . defective” arguments. We reject that argument 

for the reasons given in Part II.A of this opinion. 

 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

19

Ballast argues that ULT waived this argument. We 

agree. 

ULT waived its right to seek a new claim construction 

because ULT did not seek that construction until after 

trial. As in Broadcom Corp. v. Qualcomm Inc. this case 

“falls squarely within our holding in Eli Lilly & Company 

v. Aradigm Corporation, where a party ‘never requested 

that the district court construe any terms in the relevant 

claim and never offered a construction of that claim, but 

rather only after the presentation of all of the evidence to 

the jury . . . even suggested that claim construction 

might be helpful to determine the proper scope of the 

claimed invention.’” 543 F.3d 683, 694 (Fed. Cir. 2008) 

(quoting Eli Lilly, 376 F.3d 1352, 1360 (Fed. Cir. 2004)

(internal quotations and brackets omitted)). We hold that 

ULT has waived its right to request a construction of 

“connected to” and that ULT implicitly conceded that the 

meanings of “connected to” is clear and not in need of 

construction.

E. “CONTROL MEANS” 

ULT argues that the district erred in denying JMOL 

on the basis of infringement of the “control means” limitation under the doctrine of equivalents. ULT contends that 

it does not infringe the asserted claims because the control circuits in the accused products allow a ballast to 

continue to draw power after shutdown, a feature that 

differentiates the accused products from the “control 

means” limitation of claim 1. According to ULT, the ’529 

patent disclaims circuits like the accused circuits that 

draw power after shutdown by distinguishing such circuits from the “control means” feature. ULT also highlights a number of other ways in which ULT’s products 

differ from the “control means” limitation of claim 1.

Lighting Ballast counters that substantial evidence 

supports the jury’s finding of equivalency. According to 

Lighting Ballast, claim 1 does not require the absence of 
 LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

20

power-draw from the ballast on shutdown. Rather, Lighting Ballast explains that the “control means” feature 

must be operable to stop oscillations of the converter, a 

feature that Lighting Ballast contends the accused products share with embodiments of the ’529 Patent. Lighting 

Ballast argues that ULT confuses power draw from the 

ballast with stopping oscillations of the converter. Accordingly, Lighting Ballast contends that because ULT 

does not challenge the jury’s implicit finding that the 

accused products stop oscillations of the converter, the 

jury’s verdict is supported by substantial evidence. We 

agree with Lighting Ballast. 

A denial of a motion for JMOL is not unique to patent 

law, and thus, we apply the law of the applicable regional 

circuit, in this case the Fifth Circuit. See Transocean 

Offshore Deepwater Drilling, Inc. v. Maersk Drilling USA, 

Inc., 699 F.3d 1340, 1346-47 (Fed. Cir. 2012). Under Fifth 

Circuit law, a district court’s decision on a motion for 

JMOL is reviewed de novo, reapplying the JMOL standard. Ford v. Cimarron Ins. Co., 230 F.3d 828, 830 (5th 

Cir. 2000). JMOL is appropriate when a party has been 

fully heard on an issue and there is no legally sufficient 

evidentiary basis for a reasonable jury to find for that 

party on that issue. Fed. R. Civ. P. 50(a)(1).

ULT seeks to have this court reverse the district 

court’s opinion on JMOL regarding the “control means” 

term by reweighing the evidence produced at trial. We 

refuse to do so. The role of an appellate court is to review 

the final judgment issued by the district court. When 

final judgment is issued upon a jury verdict, this court 

can only look to whether there was substantial evidence 

to support the jury’s verdict. We may not independently 

reweigh the evidence, as ULT asks this court to do.

We conclude that the jury’s verdict is supported by 

substantial evidence. As outlined in the district court’s 

opinion, Lighting Ballast’s expert, Dr. Victor Roberts, 
LIGHTING BALLAST CONTROL LLC v. PHILIPS ELECTRONICS 

NORTH AMERICA

21

identified the structure of the accused products and 

testified that such structures were equivalent to the 

“control means” of the ’529 patent for infringement purposes. Dr. Roberts first identified where DC enters the 

“control means” and testified that the accused products 

perform the first function of the ’529 patent “control 

means” of receiving a control signal from the DC input 

terminals. Dr. Roberts then testified that the accused 

products satisfy the second function of the “control 

means” limitation because they initiate oscillations and 

stop oscillations of the converter. Dr. Roberts explained 

that the signal flows down through the resistors, through 

the discrete transistors and eventually over the integrated circuit into a pin labeled EN2, which enables oscillations. Dr. Roberts testified in detail as to the way in 

which the accused products meet the “control means”

limitation. We find that this evidence is sufficient to 

support the jury’s verdict of infringement. 

III

For these reasons, we affirm the judgment of the district court.

AFFIRMED