Document ID: s3://data.kl3m.ai/documents/govinfo/USCOURTS/USCOURTS-ca13-14-01110/USCOURTS-ca13-14-01110-0/pdf.json

Parties Involved:
FujiFilm Corporation
Appellee
FujiFilm North America Corporation
Appellee
FujiFilm USA, Inc.
Appellee
Hewlett-Packard Company
Appellee
JVC Company of America
Appellee
Matsushita Electric Industrial Co., Ltd.
Appellee
Nikon Corporation
Appellee
Nikon, Inc.
Appellee
Olympus Corp.
Appellee
Olympus Imaging America Inc.
Appellee
Panasonic Corporation
Appellee
Panasonic Corporation of North America
Appellee
Papst Licensing GmbH & Co. KG
Appellant
Samsung Opto-Electronics America, Inc.
Appellee
Samsung Techwin Co.
Appellee
Victor Company of Japan, Ltd.
Appellee

Document Text:

United States Court of Appeals 

for the Federal Circuit ______________________ 

IN RE PAPST LICENSING DIGITAL CAMERA

PATENT LITIGATION

______________________________________________________

PAPST LICENSING GMBH & CO. KG,

Plaintiff-Appellant,

v.

FUJIFILM CORPORATION, FUJIFILM NORTH 

AMERICA CORPORATION (formerly known as 

Fujifilm USA, Inc.), HEWLETT-PACKARD 

COMPANY, JVC COMPANY OF AMERICA, NIKON 

CORPORATION, NIKON, INC., OLYMPUS CORP.,

OLYMPUS IMAGING AMERICA INC., PANASONIC 

CORPORATION (formerly known as Matsushita 

Electric Industrial Co., LTD.), PANASONIC

CORPORATION OF NORTH AMERICA , SAMSUNG 

OPTO-ELECTRONICS AMERICA, INC., SAMSUNG 

TECHWIN CO., AND VICTOR COMPANY OF JAPAN, 

LTD.,

Defendants-Appellees.

______________________ 

2014-1110

______________________ 

Appeal from the United States District Court for the 

District of Columbia in No. 1:07-mc-00493-RMC, Judge 

Rosemary M. Collyer.

______________________ 

Case: 14-1110 Document: 121-2 Page: 1 Filed: 02/02/2015
2 PAPST LICENSING v. FUJIFILM CORPORATION

Decided: February 2, 2015

______________________ 

JOHN T. BATTAGLIA, Fisch Hoffman Sigler LLP, of 

Washington, DC, argued for plaintiff-appellant. With him 

on the brief were ALAN M. FISCH and ROY WILLIAM 

SIGLER. 

RACHEL M. CAPOCCIA, Alston & Bird LLP, of Los Angeles, California, argued for defendants-appellees. With 

her on the brief for Panasonic Corporation, et al., was 

THOMAS W. DAVISON. On the brief for Fujifilm Corporation, et al., were STEVEN J. ROUTH, STEN A. JENSEN, JOHN 

R. INGE and T. VANN PEARCE, JR, Orrick, Herrington & 

Sutcliffe LLP, of Washington, DC. On the brief for Nikon 

Corporation, et al., were DAVID L. WITCOFF and MARC S.

BLACKMAN, Jones Day, of Chicago, Illinois. Of counsel was 

MARRON ANN MAHONEY. On the brief for Olympus Corporation, et al., were RICHARD DE BODO and ANDREW V.

DEVKAR, Bingham McCutchen LLP, of Santa Monica, 

California. Of counsel was SUSAN BAKER MANNING, Morgan, Lewis & Bockius LLP, of Washington, DC. On the 

brief for Samsung Techwin, Co., et al., was PATRICK J.

KELLEHER, Drinker Biddle & Reath LLP, of Chicago, 

Illinois.

CHARLENE M. MORROW, Fenwick & West LLP, of 

Mountain View, California, argued for defendant-appellee 

Hewlett-Packard Company. With her on the brief were 

DAVID D. SCHUMANN and BRYAN A. KOHM, of San Francisco, CA. 

______________________ 

Before TARANTO, SCHALL, and CHEN, Circuit Judges.

TARANTO, Circuit Judge.

Papst Licensing GmbH & Co. KG owns U.S. Patent 

Nos. 6,470,399 and 6,895,449. The written descriptions 

Case: 14-1110 Document: 121-2 Page: 2 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 3

are largely the same, the ’449 patent having issued on a 

divisional application carved out of the application that 

became the ’399 patent. The focus of both patents is an 

interface device for transferring data between an input/output data device and a host computer. The current 

appeal involves whether certain digital-camera manufacturers infringe Papst’s patents. The district court, applying and elaborating on its constructions of various claim 

terms, entered summary judgment of non-infringement, 

concluding that none of the manufacturers’ accused 

products at issue here come within any of the asserted 

claims. Papst appeals five claim constructions. We agree 

with Papst that the district court erred in the identified 

respects. We therefore vacate the summary judgment of 

non-infringement. 

BACKGROUND

The ’399 and ’449 patents, both entitled “Flexible Interface for Communication Between a Host and an Analog 

I/O Device Connected to the Interface Regardless the 

Type of the I/O Device,” disclose a device designed to 

facilitate the transfer of data between a host computer

and another device on which data can be placed or from 

which data can be acquired. ’399 patent, Title and Abstract.1 The written description states that, while interface devices were known at the time of the invention, the 

existing devices had limitations, including that they 

tended to require disadvantageous sacrifices of datatransfer speed or of flexibility as to what host computers 

and data devices they would work with. ’399 patent, col. 

1, line 15, to col. 2, line 13. Thus, “standard interfaces”—

those “which, with specific driver software, can be used 

1 Because the ’399 and ’449 patents have very similar written descriptions, we cite the ’399 patent, and refer 

to a “written description” in the singular, except when 

there are important differences between the two.

 

Case: 14-1110 Document: 121-2 Page: 3 Filed: 02/02/2015
4 PAPST LICENSING v. FUJIFILM CORPORATION

with a variety of host systems”—“generally require very 

sophisticated drivers” to be downloaded onto the host 

computer, but such drivers “are prone to malfunction 

and . . . limit data transfer rates.” Id. at col. 1, lines 22–

28. On the other hand, with interface devices that “specifically match the interface very closely to individual host 

systems or computer systems,” “high data transfer rates 

are possible,” but such interface devices “generally cannot 

be used with other host systems or their use is very 

ineffective.” Id. at col. 1, line 67, to col. 2, line 7. The fast, 

host-tailored interface also “must be installed inside the 

computer casing to achieve maximum data transfer 

rates,” which is a problem for laptops and other spaceconstrained host systems. Id. at col. 2, lines 8–13.

The patents describe an interface device intended to 

overcome those limitations. It is common ground between 

the parties that, when a host computer detects that a new 

device has been connected to it, a normal course of action 

is this: the host asks the new device what type of device it 

is; the connected device responds; the host determines 

whether it already possesses drivers for (instructions for 

communicating with) the identified type of device; and if 

it does not, the host must obtain device-specific drivers 

(from somewhere) before it can engage in the full intended 

communication with the new device. In the patents at 

issue, when the interface device of the invention is connected to a host, it responds to the host’s request for 

identification by stating that it is a type of device, such as 

a hard drive, for which the host system already has a 

working driver. By answering in that manner, the interface device induces the host to treat it—and, indirectly,

data devices on the other side of the interface device, no 

matter what type of devices they are—like the device that 

is already familiar to the host. Thereafter, when the host 

communicates with the interface device to request data 

from or control the operation of the data device, the host 

uses its native device driver, and the interface device 

Case: 14-1110 Document: 121-2 Page: 4 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 5

translates the communications into a form understandable by the connected data device. See id. at col. 3, line 25, 

to col. 5, line 32.

The interface device of the invention thus does not require that a “specially designed driver” for the interface 

device be loaded into a host computer—neither a “standard” one to be used for a variety of hosts nor one customized for a particular host. Id. at col. 5, line 15. Instead, it 

uses a host’s own familiar driver, which (as for a hard 

drive) often will have been designed (by the computer 

system’s manufacturer) to work fast and reliably. The 

result, says the written description, is to allow data 

transfer at high speed without needing a new set of 

instructions for every host—“to provide an interface 

device for communication between a host device and a 

data transmit/receive device whose use is host deviceindependent and which delivers a high data transfer 

rate.” Id. col. 3, lines 25–28.

Claim 1 of the ’399 patent sets forth the specifics of 

the claimed interface device:

1. An interface device for communication between a host device, which comprises drivers for 

input/output devices customary in a host device 

and a multi-purpose interface, and a data 

transmit/receive device, the data transmit/receive device being arranged for providing 

analog data, comprising: 

a processor; 

a memory; 

a first connecting device for interfacing the host 

device with the interface device via the multipurpose interface of the host device; and 

a second connecting device for interfacing the 

interface device with the data transmit/receive 

Case: 14-1110 Document: 121-2 Page: 5 Filed: 02/02/2015
6 PAPST LICENSING v. FUJIFILM CORPORATION

device, the second connecting device including a 

sampling circuit for sampling the analog data 

provided by the data transmit/receive device and 

an analog-to-digital converter for converting data 

sampled by the sampling circuit into digital data, 

wherein the interface device is configured by the 

processor and the memory to include a first command interpreter and a second command interpreter, 

wherein the first command interpreter is configured in such a way that the command interpreter, 

when receiving an inquiry from the host device as 

to a type of a device attached to the multi-purpose 

interface of the host device, sends a signal, regardless of the type of the data transmit/receive device attached to the second 

connecting device of the interface device, to the 

host device which signals to the host device that it 

is an input/output device customary in a host 

device, whereupon the host device communicates 

with the interface device by means of the driver 

for the input/output device customary in a host 

device, and 

wherein the second command interpreter is configured to interpret a data request command from 

the host device to the type of input/output device 

signaled by the first command interpreter as a data transfer command for initiating a transfer of 

the digital data to the host device.

Id. col. 12, line 42, to col. 13, line 13 (emphases added to 

highlight language of particular significance to the issues 

on appeal). Claim 1 of the ’449 patent is similar, but it 

does not require the data device to be an analog device, 

and it requires the interface device to respond to the host 

that it is a storage device. ’449 patent, col. 11, line 46, to 

Case: 14-1110 Document: 121-2 Page: 6 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 7

col. 12, line 6. A few other differences between the claims 

are discussed infra. 

Beginning in 2006, Papst sent letters to major digitalcamera manufacturers, accusing them of infringing its 

patents and requesting that they enter into negotiations 

to license its inventions. One of the manufacturers sued 

Papst in the United States District Court for the District 

of Columbia, seeking a declaratory judgment of noninfringement. In 2008, Papst filed infringement suits 

against the camera manufacturers in multiple district 

courts across the country. A multi-district litigation panel 

then consolidated all cases and transferred them to the 

D.C. district court. 

In preparation for claim construction, the district 

court received a “tutorial” from the parties’ experts, whom 

the court asked to be “neutral” and who addressed the 

background of the technology, how the claimed inventions 

work, and other technical understandings, but not whether any particular term in the patent or the prior art has a 

particular meaning in the relevant field. J.A. 1596–97; 

see In re Papst Licensing GmbH & Co. KG Litig., No. 07-

mc-00493 (D.D.C. June 6, 2008) (order specifying scope of 

tutorial). The court then heard extensive argument from 

counsel, but it declined to admit expert testimony or to 

rely on an expert declaration from Papst, stating that “the 

intrinsic evidence—the claims, the specification, and the 

prosecution history—provide the full record necessary for 

claims construction.” J.A. 1597. 

The court issued its initial claim-construction order in 

2009. It issued a modified claim-construction order after 

additional briefing. The district court then ruled on eight

summary-judgment motions filed by the camera manufacturers, treating the manufacturers as two distinct 

groups—one group consisting of Hewlett-Packard Co. 

(“HP”), the other of all other accused manufacturers 

(“Camera Manufacturers”). As detailed in our discussion 

Case: 14-1110 Document: 121-2 Page: 7 Filed: 02/02/2015
8 PAPST LICENSING v. FUJIFILM CORPORATION

infra, the court’s rulings on summary judgment clarified 

what it understood some of its claim constructions to 

mean. With respect to the accused products now at issue, 

the combined effect of the court’s summary-judgment 

rulings was a determination of non-infringement by the 

Camera Manufacturers and HP. The court ultimately 

entered a final judgment of non-infringement under 

Federal Rule of Civil Procedure 54(b) for both HP and the 

Camera Manufacturers, In re Papst Licensing GmbH & 

Co. KG Litig., 987 F. Supp. 2d 58, 62 (D.D.C. 2013), 

having severed certain other claims, In re Papst Licensing 

GmbH & Co. KG Litig., 967 F. Supp. 2d 63, 65 n.2, 71 

(D.D.C. 2013). 

Papst appeals, arguing that the court’s summaryjudgment orders should be reversed because they rely on 

incorrect constructions of five different terms from 

the ’399 and ’449 patents. We have jurisdiction under 28 

U.S.C. § 1295(a)(1). 

DISCUSSION

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

by the district court. See Bender v. Dudas, 490 F.3d 1361, 

1366 (Fed. Cir. 2007). The infringement inquiry, which 

asks if an accused device contains every claim limitation 

or its equivalent, Warner-Jenkinson Co. v. Hilton Davis 

Chem. Co., 520 U.S. 17, 29 (1997), depends on the proper 

construction of the claims. See Cybor Corp. v. FAS Techs., 

Inc., 138 F.3d 1448, 1454 (Fed. Cir. 1998) (en banc). In 

this case, we review the district court’s claim constructions de novo, because intrinsic evidence fully determines 

the proper constructions. See Teva Pharm. U.S.A. Inc. v. 

Sandoz, Inc., 135 S. Ct. 831, 840–42 (2015). As we have 

noted, the district court relied only on the intrinsic record, 

not on any testimony about skilled artisans’ understandings of claim terms in the relevant field, and neither party 

challenges that approach.

Case: 14-1110 Document: 121-2 Page: 8 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 9

Two clarifications simplify our analysis so that it is 

enough for us to address the correctness of the district 

court’s constructions. First, the parties have not presented developed arguments other than arguments about the 

choice, on each issue, between the district court’s construction and the alternative construction by Papst that 

the district court rejected. Specifically, for none of the 

issues have the parties identified a third possibility and 

both elaborated an argument for such a possibility and 

explained the importance to the case of considering it. 

Second, it is undisputed that if we reject all five of the 

challenged constructions, the summary-judgment orders 

must be vacated.2

We reject the five constructions at issue. We do so following our familiar approach to claim construction. “We 

generally give words of a claim their ordinary meaning in 

the context of the claim and the whole patent document; 

the specification particularly, but also the prosecution 

history, informs the determination of claim meaning in 

context, including by resolving ambiguities; and even if 

the meaning is plain on the face of the claim language, 

the patentee can, by acting with sufficient clarity, disclaim such a plain meaning or prescribe a special definition.” World Class Tech. Corp. v. Ormco Corp., 769 F.3d 

1120, 1123 (Fed. Cir. 2014); see Phillips v. AWH Corp., 

415 F.3d 1303, 1312–17 (Fed. Cir. 2005) (en banc); Thorner v. Sony Computer Entm’t Am. LLC, 669 F.3d 1362, 

1365 (Fed. Cir. 2012). We apply, in particular, the principle that “[t]he construction that stays true to the claim 

language and most naturally aligns with the patent’s 

description of the invention will be, in the end, the correct 

construction.” Renishaw PLC v. Marposs Societa’ per 

2 If some aspects of the summary-judgment orders 

are unaffected by our claim-construction rulings, they 

may, to that extent, be reinstated on remand. 

 

Case: 14-1110 Document: 121-2 Page: 9 Filed: 02/02/2015
10 PAPST LICENSING v. FUJIFILM CORPORATION

Azioni, 158 F.3d 1243, 1250 (Fed. Cir. 1998), adopted by 

Phillips, 415 F.3d at 1316. 

On remand, this case will proceed in light of our 

claim-construction reversals. For that reason, it is worth 

reiterating that a district court may (and sometimes 

must) revisit, alter, or supplement its claim constructions

(subject to controlling appellate mandates) to the extent 

necessary to ensure that final constructions serve their 

purpose of genuinely clarifying the scope of claims for the 

finder of fact. See O2 Micro Int’l Ltd. v. Beyond Innovation Tech. Co., 521 F.3d 1351, 1359 (Fed. Cir. 2008);

Pfizer, Inc. v. Teva Pharm., USA, Inc., 429 F.3d 1364, 

1377 (Fed. Cir. 2005). That determination is to be made 

as the case moves forward.

A 

Papst first challenges the district court’s “memory 

card” summary judgment as relying on an improper 

construction of the term “interface device” found in the 

preamble of claims in both patents. The district court 

construed the term as limiting the claims’ coverage to 

“stand-alone device[s].” In re Papst Licensing GmbH & 

Co. KG Litig., 670 F. Supp. 2d 16, 31–35 (D.D.C. 2009) 

(“Claim Constr. Op.”). In particular, the court held that 

“the data transmit/receive device must be a separate 

device from the” claimed “interface device.” Id. at 33. 

Subsequently, in granting summary judgment, the court 

explained that what it meant by this requirement is that 

the interface device may not be “a permanent part of 

either the data transmit/receive device or the host device/computer,” by which it meant that it may not be 

located permanently inside the housing of either of those 

two devices. In re Papst Licensing GmbH & Co. KG Litig., 

932 F. Supp. 2d 14, 18, 21–22 (D.D.C. 2013). 

Case: 14-1110 Document: 121-2 Page: 10 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 11

1 

As a threshold matter, the Camera Manufacturers argue that we should not reach this issue because the 

district court’s summary-judgment rulings do not depend

on the construction of “interface device.” They invoke 

principles stated in SanDisk Corp. v. Kingston Technology 

Co., 695 F.3d 1348, 1354 (Fed. Cir. 2012) (“[W]here, as 

here, a party’s claim construction arguments do not affect 

the final judgment entered by the court, they are not 

reviewable.”), and Mangosoft, Inc. v. Oracle Corp., 525 

F.3d 1327, 1330 (Fed. Cir. 2008) (“we review judgments, 

not opinions”). We conclude, however, that the premise 

for invoking the cited principles is missing here. 

The district court’s summary-judgment order regarding memory-card devices shows that its final judgment

did turn on the construction of “interface device.” The 

primary reason the court gave for rejecting Papst’s infringement contentions was that “[t]he Court made clear 

in its claims construction opinion that the interface device 

is separate and distinct from the data transmit/receive 

device.” Papst, 932 F. Supp. 2d at 21. The court cited 

repeatedly to the portion of its claim-construction opinion 

addressing “interface device.” E.g., id. at 18 (citing Claim

Constr. Op. at 32–35); id. at 21 (citing Claim Constr. Op.

at 34–35); id. at 23 (citing Claim Constr. Op. at 31–35). 

And in its opening paragraphs, the court summarized the

Camera Manufacturers’ position on summary judgment 

as relying on that same construction. Id. at 16 (“Because 

the invented ‘interface device’ is a stand-alone device that 

is separate and apart from any data transmit/receive 

device, the Camera Manufacturers contend that a 

memory card cannot be both part of the interface device 

and a data transmit/receive device . . . .”). In these circumstances, we will consider whether the district court’s 

construction is correct.

Case: 14-1110 Document: 121-2 Page: 11 Filed: 02/02/2015
12 PAPST LICENSING v. FUJIFILM CORPORATION

2 

We hold that the term “interface device” is not limited 

to a “stand-alone device” in the district court’s sense 

relied on for summary judgment: a device that is physically separate and apart from, and not permanently attached 

to, a data device (or a host computer). Representative 

claim 1 of the ’449 patent begins, “[a]n interface device . . . 

comprising the following features,” and then recites the 

necessary components of the claimed interface device. See 

supra pp. 5–6. Neither the claim language nor the rest of 

the intrinsic record supports the district court’s exclusion 

of a device that performs the required interface functions 

and is installed permanently inside the housing of a 

particular data device.

The district court did not suggest that the term “interface device” by itself implied its construction. Rather, 

it heavily relied for its construction on the specific claim 

requirement that (to paraphrase) a part of the interface, 

upon receiving an identification query from the host 

computer, send a signal identifying itself as a hostfamiliar device “regardless of the type of the data transmit/receive device attached to the second connecting 

device of the interface device.” ’449 Patent, col. 11, lines 

63–65. The court concluded that the “regardless” phrasing in the claim “strongly indicates that various kinds of 

data transmit/receive devices could be attached” to the 

interface device. Claim Constr. Op. at 32–33. 

But the court’s construction does not follow from its 

understanding of the “regardless” phrase. Nothing about 

that phrase forbids any single instance of the claimed 

interface device to be permanently attached to a particular data device. It readily allows permanent attachment 

of each copy of the interface device to a particular data 

device, prescribing only that the same host-responsive 

identification signal be sent regardless of what type of 

data device the interface device is attached to. That is, 

Case: 14-1110 Document: 121-2 Page: 12 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 13

there can be multiple copies of the same interface device, 

with each permanently attached to one of a variety of 

different data devices. The claim language, in short, does 

not limit “interface device” to a device not permanently 

attached to (readily detachable from) a data device. 

The written description does not do so either. Critically, the district court’s construction, like the Camera 

Manufacturers’ arguments supporting it, fundamentally 

mistakes what the description makes clear is the stated 

advance over the prior art. As explained supra, the 

described advance over the prior art was the elimination 

of the need for special drivers to be placed on the host 

computer by instead having the host computer use a 

single, already-present, fast, reliable driver to communicate with the interface and, through it, with the data 

device, which need not be of a particular type. Nothing 

about that advance suggests exclusion of a permanent 

attachment of such an interface to the data device—a 

construction that is “unmoored from, rather than aligned 

with” what is described as the invention’s advance. World 

Class Tech., 769 F.3d at 1124. 

No passage in the written description says otherwise. 

The Camera Manufacturers cite passages that describe 

the invention as “sufficiently flexible to permit attachment of very different electrical or electronic systems to a 

host device.” ’399 patent, col. 1, lines 56–59; id., col. 7, 

lines 45–49 (touting the “present invention” as allowing 

“an interface between a host device and almost any data 

transmit/receive device”). But that language does not 

speak to the connection between the interface and data 

devices. Rather, it addresses the connection between the 

host computer and data devices, a connection facilitated 

by the interface device. Even as to that, the passage may 

be read merely to assert the capability of one-to-one hostto-data-device connections, with the data device chosen 

from a wide variety of possible data devices. But even if it 

is read to assert a capability of one-to-many host-to-dataCase: 14-1110 Document: 121-2 Page: 13 Filed: 02/02/2015
14 PAPST LICENSING v. FUJIFILM CORPORATION

device connections, it says nothing to assert that a given 

copy of the interface device must be attachable to different data devices either simultaneously or seriatim. 

The Camera Manufacturers also point to the written 

description’s statement that “[i]n the interface device 

according to the present invention an enormous advantage is to be gained . . . in separating the actual hardware required to attach the interface device to the data 

transmit/receive device from the communication 

unit,” ’399 patent, col. 8, lines 23–28 (figure numbers 

removed)—which they say means that permitting multiple data devices to attach to a single interface device is an 

integral part of the invention. But that passage does not 

support the district court’s limiting construction, and not 

only because it is part of the description of several preferred embodiments, rather than a clear declaration of 

what constitutes an essential part of the invention. 

The full passage makes clear that the “hardware separation” is not between the interface and data device, but 

within the interface device itself—between the second 

connecting device, on one hand, and “the digital signal 

processor, the memory means[,] and the first connecting 

device,” on the other. Id., col. 8, lines 28–29 (figure numbers removed). When the passage states that this separation “allows a plurality of dissimilar device types to be 

operated in parallel in identical manner,” it immediately 

adds: “Accordingly, many interface devices can be connected to a host device which then sees many different ‘virtual’ hard disks.” Id. col. 8, lines 30–33 (emphasis added). 

The suggestion is that distinct interface devices are used 

for distinct data devices, each interface device incorporating a “second connecting device” that works for its particular data device. This suggestion works against, rather 

than supports, the Camera Manufacturers’ view of multiple data devices attached to a single (separate) interface 

device, whether at once or in sequence, for it readily 

accommodates a one-to-one permanent attachment of an 

Case: 14-1110 Document: 121-2 Page: 14 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 15

interface device to a data device. And the parallel operation of dissimilar device types is possible because the 

invention causes the host computer to use its native

software to transfer data at high speed and because the 

invention creates a uniform interface from the host’s 

perspective for controlling the data device. See, e.g., ’399 

patent, col. 7, lines 45–49. 

Finally, nothing in the prosecution history supports 

the district court’s narrow construction. The Camera 

Manufacturers point to an amendment that changed the

claim language from “the type of a device attached” to “a 

type of device attached” in what became claim 1 of the 

’399 patent. J.A. 391. But there was no accompanying 

explanation of the change, which, on its face, does nothing 

more than the “regardless” language of claim 1 does, and 

that language, as we have explained, does not forbid 

permanent attachment. The Camera Manufacturers also 

note that the applicant stated that “it is clear that the 

data transmit/receive device to be connected to the second 

connecting device of the subject interface provides analog 

data.” J.A. 389 (emphasis added). Nothing in that statement precludes the connection from being permanent once 

made. 

B 

Papst also appeals the district court’s construction of 

the phrase “second connecting device,” which appears in 

both patents.3 The district court construed the term as “a 

physical plug or socket for permitting a user readily to 

3 The ’399 and ’449 patent claims use slightly different language, but neither party suggests that the 

difference affects the proper construction of “second 

connecting device.” Nor does either party argue that the 

claim language is means-plus-function language under 

what is now codified as 35 U.S.C. § 112(f).

 

Case: 14-1110 Document: 121-2 Page: 15 Filed: 02/02/2015
16 PAPST LICENSING v. FUJIFILM CORPORATION

attach and detach the interface device with a plurality of 

dissimilar data transmit/receive devices.” Claim Constr. 

Op. at 43. The parties’ arguments over the proper construction of “second connecting device” largely mirror the 

arguments over whether the interface device must be 

readily detachable from the data device. See Camera 

Manufacturers’ Br. 68 (“As explained above, the claim 

language requires the interface device to be connectable 

to many different types of [data devices].”); HP’s Br. 3 

(“Core to the invention is the ability to attach the interface device to different or multiple data transmit/receive 

devices.”). The district court likewise tied its construction 

of “second connecting device” to its understanding that 

the interface device must be a stand-alone one readily 

attachable to and detachable from multiple data devices. 

See Claim Constr. Op. at 42, 44. 

We conclude that the district court’s construction of 

“second connecting device” is incorrect largely for reasons 

we have given for rejecting the “interface device” construction. The district court did not conclude, and the 

Camera Manufacturers and HP have not meaningfully 

argued, that the ordinary meaning of “second connecting 

device” (or “connecting device”) requires a physical plug, 

socket, or other structure that permits a user to readily 

attach and detach something else. The principal basis for 

the district court’s inclusion of those requirements was 

the basis we have already rejected—the view that other 

claim language and the written description require the

interface device (of which the second connecting device is 

a part, according to the claims) to be stand-alone. For 

“second connecting device,” the district court added that a 

preferred embodiment from the written description includes pin connectors and other socket-like structures. 

See Claim Constr. Op. at 42–44. But we see nothing to 

take that embodiment outside the reach of the usual rule 

that claims are generally not limited to features found in 

what the written description presents as mere embodiCase: 14-1110 Document: 121-2 Page: 16 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 17

ments, where the claim language is plainly broader. 

Phillips, 415 F.3d at 1323. 

C 

The district court’s construction of the phrase “data 

transmit/receive device” is challenged here as well. The 

district court construed the phrase to mean “a device that 

is capable of either (a) transmitting data to or (b) transmitting data to and receiving data from the host device 

when connected to the host device by the interface device.” 

Claim Constr. Op. at 39 (emphasis added). The parties’ 

dispute focuses on the “when connected” portion of the 

court’s construction, which the district court understood 

to require that the data device be capable of transmitting 

data while connected to the host, that is, able to begin 

transmitting after the interface device is connected to the 

host device. In re Papst Licensing GmbH & Co. KG Litig., 

967 F. Supp. 2d 1, 6–7 (D.D.C. 2013). We reject that 

portion of the court’s construction.

1 

The Camera Manufacturers initially argue that Papst 

may not challenge the district court’s construction because “the district court adopted word-for-word the construction of [data transmit/receive device] that Papst 

proposed.” Camera Manufacturers’ Br. 47. That is an 

unreasonable characterization of what occurred in the 

district court. The Camera Manufacturers, not Papst, 

proposed the bulk of the court’s construction, including 

the “when connected” language. Claim Constr. Op. at 37. 

Papst proposed a construction without the “when connected” language, opposing inclusion of that language. Claim 

Constr. Op. at 37 (noting “Papst objects to any construction” but argues in the alternative “that the term may be 

construed ‘for context’ as ‘a device that receives input and 

provides data to the interface device’” (citation omitted)). 

When the district court adopted the Camera Manufacturers’ “when connected” language, Papst noticed that the 

Case: 14-1110 Document: 121-2 Page: 17 Filed: 02/02/2015
18 PAPST LICENSING v. FUJIFILM CORPORATION

adopted construction, in a respect distinct from the “when 

connected” dispute, rested on a misunderstanding of a 

patent figure, and it filed a motion identifying the alleged 

error and asking the court to modify the adopted construction in the one respect needed to correct it. Papst 

limited its motion to that point, leaving the other, already-contested aspects of the claim construction untouched. The district court agreed with Papst and fixed 

the construction as urged. Claim Constr. Op. at 39.

The Camera Manufacturers argue that Papst, having 

unsuccessfully opposed a construction with the “when 

connected” language, lost its ability to challenge the 

adoption of the “when connected” language by not reraising the issue when seeking a modification based on a 

newly identified issue. See Oral Argument at 33:44–34:10

(arguing that Papst forfeited its challenge because it 

requested a modification without “reserv[ing] the ability 

to go back later to ask for [its] old construction”). This 

contention is wholly without merit. In the district court, 

Papst opposed the construction it now opposes, and it was 

not required to state its opposition twice. Papst could not 

have given the district court the impression that it suddenly supported the construction when, in seeking a 

modification, it limited its request to a manifest error

resting on a plain misapprehension of the record, rather 

than rehashing the broader arguments on claim construction that the court had fully considered. Papst’s limited 

approach in seeking a modification was, indeed, commendably consistent with the general anti-repetition 

principle governing requests for reconsideration. See Isse 

v. Am. Univ., 544 F. Supp. 2d 25, 29–30 (D.D.C. 2008) 

(“‘[W]here litigants have once battled for the court’s 

decision, they should neither be required, nor without 

good reason permitted, to battle for it again.’” (citation 

omitted)). 

Case: 14-1110 Document: 121-2 Page: 18 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 19

2 

We conclude that the data transmit/receive device recited in the preamble to the claims of the ’399 and ’449 

patents need not be capable of communicating “when 

connected to the host device by the interface device.” (The 

parties do not dispute that this language, though appearing in the preamble, is a claim limitation. We proceed on 

the assumption that it is.) Nothing about the ordinary 

meaning of “data transmit/receive device” suggests any 

temporal constraint on the transferring of data. As the 

words imply, a data transmit/receive device is a device 

that may transmit or receive data; those words offer no 

information about when data is transferred. 

To the extent that some claim language does suggest 

a temporal constraint, the focus is always on communications between the interface device and the host computer, 

not between the data device and the host computer. For 

example, the interface device must send a signal to the 

host device “when receiving an inquiry from the host 

device as to a type of a device attached.” ’399 patent, col. 

12, line 65, to col. 13, line 3. After the interface device 

signals to the host device, the interface device must be 

able to receive communications from the host device. Id. 

col. 13, lines 5–8 (“whereupon the host device communicates with the interface device”). But the claims of both 

patents are silent as to when the interface device must 

communicate with the data device. If anything, claim 1 of 

the ’399 patent tends to suggest that data can already 

have been transferred to the interface device from the 

data device before it is requested by the host computer: 

claim 1 says that the interface device must “interpret a 

data request command from the host device . . . as a data 

transfer command for initiating a transfer of the digital 

data to the host device.” Id. col. 13, lines 10–13 (emphasis 

added). Because claim 1 is limited to interface devices 

that receive analog data from a data device and then 

convert it to digital data, the quoted language seems to 

Case: 14-1110 Document: 121-2 Page: 19 Filed: 02/02/2015
20 PAPST LICENSING v. FUJIFILM CORPORATION

contemplate that the initiated transfer is of pre-converted 

digital data stored on the interface device. Regardless, 

the claim language nowhere requires the interface device 

to be capable of receiving data that moves from the data 

device after connecting to the host. 

The Camera Manufacturers offer no persuasive argument for why the claim language or any other part of 

the specification or prosecution history requires that a 

data device be able to communicate with the host “when 

connected to the host device by the interface device.” At 

most they assert, without significant elaboration, that the 

“specification nowhere discloses indefinite storage by the 

interface device of data from a [data device].” Camera 

Manufacturers’ Br. 51. This assertion does not suggest a 

disclaimer of any sort; it merely asserts an absence of 

something in the written description. But that absence 

must be judged in light of what is plainly present in the 

written description—a disclosure of memory that is part 

of the interface device. ’399 patent, col. 5, line 52, and 

Figure 1. And we have been given no reason at all to 

infer, from the absence of more express statements regarding use of the disclosed memory in the interface

device for temporary storage of data from the data device, 

that the claim should be read to include a textually unsupported “when connected” requirement regarding 

transfer of data to or from the data device. 

The district court, when construing the data-device 

claim language, focused almost exclusively on whether 

the data device must be capable of both sending and 

receiving data. It did not lay out good reasons for adopting the “when connected” requirement as part of its 

construction. Claim Constr. Op. at 37–39; In re Papst 

Licensing GmbH & Co. KG Litig., 624 F. Supp. 2d 54, 75–

77 (D.D.C. 2009). Finding no basis for that requirement, 

we conclude that the court erred by including that phrase 

in its construction. 

Case: 14-1110 Document: 121-2 Page: 20 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 21

D 

The next issue we discuss is the district court’s construction of the phrase “virtual files” in the ’399 patent 

and the phrase “simulating a virtual file system” in 

the ’449 patent.4 The district court construed “virtual 

files” as “files that appear to be but are not physically 

stored; rather, they are constructed or derived from 

existing data when their contents are requested by an 

application program so that they appear to exist as files 

from the point of view of the host device.” Claim Constr. 

Op. at 60. The court construed “simulating a virtual file 

system” almost identically as “appearing to be a system of 

files, including a directory structure, that is not physically 

stored; rather, it is constructed or derived from existing 

data when its contents are requested by an application 

program so that it appears to exist as a system of files 

from the point of view of the host device.” Id. at 61. The 

district court understood its construction to limit the 

“virtual files” of the “virtual file system” to files “not 

physically stored on the interface device,” whose content

is data “originating from the data transmit/receive device.” In re Papst Licensing GmbH & Co. KG Litig., 967 

F. Supp. 2d 48, 56 (D.D.C. 2013). We reverse.

The core of the parties’ disagreement is whether the 

“existing data” from which the virtual files are “construct4 The district court did not rely on the construction 

of “virtual files” in the ’399 patent in any of its summaryjudgment motions. The term appears only in dependent 

claims 7–10 of that patent, which the district court never 

addressed because it found that the accused devices lack 

elements of the independent claims. Nevertheless, because the construction of “virtual files” is bound up with 

the construction of “simulating a virtual file system” in 

the ’449 patent, and because the construction may be 

important on remand, we address both phrases now.

 

Case: 14-1110 Document: 121-2 Page: 21 Filed: 02/02/2015
22 PAPST LICENSING v. FUJIFILM CORPORATION

ed or derived” may already exist on the interface device 

when the host requests the virtual file. Although framed 

in different ways by the parties, the disagreement is 

similar to the dispute over the “when connected” language 

of the district court’s construction of “data transmit/receive device.” The Camera Manufacturers argue 

that “virtual files” cannot contain data already existing 

physically on the claimed interface device; rather, the 

data in such files must be present only on the data device, 

not the interface device, when requested by the host 

device. Papst argues that the phrases “virtual files” and 

“simulating a virtual file system” allow the virtual files to 

be derived from data already physically stored on the 

interface device when the host requests the relevant 

virtual file. 

We agree with Papst. Nothing in the claims or written description limits a “virtual file” to one whose content 

is stored off the interface device, though it includes such 

files. “Virtual” conveys some kind of as if action, one 

thing emulating another; the term was prominently used 

that way in the computer field at the time of the inventions here. See CardSoft v. Verifone, Inc., 769 F.3d 1114, 

1117–18 (Fed. Cir. 2014) (discussing Java Virtual Machine in patent dating to 1998). What is crucial is how 

the patent identifies the emulation. In the present context, the emulation does not turn on whether data in a 

“virtual file” is physically located in the interface device or 

a data device when the host seeks it.

As we have explained, what the patent describes as 

the advance over prior art is the use of a host-native 

driver for obtaining access to data even when the data is 

not actually on a device of the type for which that driver 

was designed—in the featured example, not actually on a 

hard drive. Nothing in the written description suggests 

that this depends on what non-host physical memory 

units hold the data as long as the interface device mimics

the data-organizational tools expected by the host-native 

Case: 14-1110 Document: 121-2 Page: 22 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 23

driver, such as directory structures for a hard-disk drive, 

to enable the host to gain access to it. To impose the 

district court’s requirement tied to physical location is to 

introduce a meaning of “virtual” that is foreign to what is 

described as the invention’s advance. An interface device 

file is “virtual” in the only way relevant to the invention 

when it organizes data in a manner that allows the host

to use its native driver to gain access to the data even if 

the data is not actually on a device for which the native 

driver was designed—regardless of where else that data 

may be. 

The written description uniformly speaks of the “virtual” files in such data-organization terms, regardless of 

physical location in the memory of the interface device or 

on the data device. For example, the interface device may 

“simulate[] a hard disk with a root directory whose entries 

are ‘virtual’ files,” though no hard disk is in fact present. ’399 patent, col. 6, lines 1–3. Similarly, in one 

embodiment the host device, during its boot sequence 

(system startup), sends a request to which the interface 

device responds with “a virtual boot sequence,” causing

the host to “assume[] that the interface device according 

to a preferred embodiment of the present invention is a 

hard disk drive.” Id. lines 26–35 (figure numbers removed). Thereafter, the interface device supplies the host 

with data-organization responses consistent with a hard 

disk, including “the directory structure of the virtual hard 

disk.” Id. lines 40–44. The written description elsewhere 

states that, “due to the simulation of a virtual mass 

storage device, the data is managed and made available 

in such a way that it can be transferred directly to other 

storage media, e.g.[,] to an actual hard disk of the host 

device.” Id. col. 8, lines 50–55; see also id. col. 12, lines 

26–29 (“[B]y simulating a virtual mass storage device, the 

interface device is automatically supported by all known 

host systems without any additional sophisticated driver 

software.” (figure numbers removed)). While all of these 

Case: 14-1110 Document: 121-2 Page: 23 Filed: 02/02/2015
24 PAPST LICENSING v. FUJIFILM CORPORATION

examples discuss the organizational structure that the 

interface device conveys to the host device, not one mentions where data physically resides.

The point is reinforced by “[o]ther claims of the patent[s] in question.” Phillips, 415 F.3d at 1314. Claim 1 

of the ’449 patent requires a “virtual file system including 

a directory structure.” ’449 patent, col. 12, lines 5–6. 

Claim 2 explains the types of files that may appear in the 

directory structure: “the directory structure has a configuration file . . . or an executable or a batch file . . . or a data 

file . . . or a help file.” Id. col. 12, lines 8–13. Enumerating those types of files as part of the virtual file system 

suggests that virtual files may include data physically 

stored on the interface device, particularly if the interface 

device is stand-alone, which it may be. For example, the 

“help file” is “for giving help on handling the interface 

device.” Id. col. 12, lines 12–13. A logical place to store 

such a file, as indicated by the written description, is on 

the interface device. See id. col. 11, line 37 (referring to 

“[h]elp files included on the interface device”). So too with 

a “configuration file” for “setting and controlling the 

functions of the interface device.” Id. col. 12, lines 8–9. 

And the written description makes clear that the data for 

those files may be stored directly on the interface device. 

See, e.g., id. col. 6, lines 50–54 (explaining that storing 

files, like the configuration file, “in the memory means of 

the interface device” allows “any enhancements or even 

completely new functions of the interface device [to] be 

quickly implemented” (figure numbers removed)); id. lines 

61–67 (“[I]nstallation [on the host device] of certain 

routines which can be frequently used . . . is rendered 

unnecessary as the EXE files are already installed on the 

interface device and appear in the virtual root directory . . . .” (emphasis added; figure numbers removed)). 

Those passages appear at column 7 of the ’399 patent as 

well, and a similar analysis applies to claims 7–10 of 

the ’399 patent. See ’399 patent, col. 13, lines 33–51.

Case: 14-1110 Document: 121-2 Page: 24 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 25

The written description does refer to one type of virtual file as a “real-time input” file, where the host computer can request a portion of the data from the real-time 

input file “whereupon data commences to be received via 

the second connecting device and data commences to be 

sent to the host device via the first connecting device.” Id. 

col. 7, lines 17–22. The written description’s discussion of 

real-time input files shows that a virtual file may be 

constructed from data residing on the data device. But 

nothing in the written description limits virtual files to 

that arrangement. Files whose content resides on the 

interface device are just as virtual in the relevant respect: 

they are accessible by the host’s use of the same driver it 

would use if they were present on the actual device for 

which the host driver was created even when they are not.

E 

Finally, Papst appeals the district court’s construction 

of the term “input/output device customary in a host 

device” in the ’399 patent and the term “storage device 

customary in a host device” in the ’449 patent. The district court construed the ’399 term to be a “data input/output device that was normally present within the 

chassis of most commercially available computers at the 

time of the invention.” Claim Constr. Op. at 55. The 

court’s construction for the ’449 patent is identical, except 

that the words “data input/output” are replaced with the 

word “storage.” Id. 

When a host computer asks the claimed interface device what type of device it is, the interface device must 

respond that it is an “input/output device customary in a 

host device” so that the host will communicate with the 

interface device using the host’s native software for that 

type of device. The parties disagree over whether the 

claims require that the device the interface device says it 

is be a type of device “normally present within the chassis” of a computer. We hold that the claims are not so 

Case: 14-1110 Document: 121-2 Page: 25 Filed: 02/02/2015
26 PAPST LICENSING v. FUJIFILM CORPORATION

limited. The written description makes clear that it is 

enough for the device to be one that was normally part of 

commercially available computer systems at the time of 

the invention.

Claim 1 of the ’399 patent uses the phrase “input/output device[s] customary in a host device” three 

times, first in the preamble when it explains that the host 

device comprises “drivers for input/output devices customary in a host device,” then twice when it defines how 

the interface device and the host computer communicate—the interface device “signals to the host device that 

it is an input/output device customary in a host device,” 

thereby prompting the host to “communicat[e] with the 

interface device by means of the driver for the input/output device customary in a host device.” This 

language does not carry a plain, precise meaning of physical location inside the chassis. The phrase “customary in 

a host device” is not especially precise, and it seems to 

emphasize what is customary, not whether the unit is 

inside or outside the device. It contrasts with, for example, “customarily found in” or simply “input/output device 

in a host device”—which have a greater suggestion of 

location, though themselves perhaps not definitively so.

For these reasons, we turn to the written description, 

which clearly evinces the intended meaning—and meets 

even the standard for overriding a seemingly plain meaning of the claim language. The written description shows 

that the “in” from “customary in” does not imply physical

location inside a computer chassis. Most starkly, the 

patent explains that “[d]rivers for input/output devices 

customary in a host device . . . are, for example, drivers for 

hard disks, for graphics devices[,] or for printer devices.” ’399 patent, col. 4, lines 27–30 (emphases added). By 

its structure—“drivers for X are, for example, drivers for 

1, 2, and 3,” thus equating X with 1, 2, and 3—the sentence clearly means that, notably, a printer device is an 

example of an “input/output device customary in a host 

Case: 14-1110 Document: 121-2 Page: 26 Filed: 02/02/2015
PAPST LICENSING v. FUJIFILM CORPORATION 27

device.” No one contends that a printer device was physically located inside the chassis of a computer at the time 

of the invention.

In addition, a preferred embodiment of the invention 

includes “a 25-pin D-shell connector to permit attachment 

to a printer interface of a host device[,] for example.” Id.

col. 9, lines 43–48 (figure numbers removed); see also id., 

Figure 2 (illustrating the D-shell printer connector). The 

clear implication is that the preferred embodiment allows 

the interface device to connect to the printer interface of 

the host computer because the interface device can inform 

the host computer that it is a printer and that the host 

should communicate with it using its built-in printer 

drivers. We do not generally construe the claims of a 

patent to exclude a preferred embodiment. Adams Respiratory Therapeutics, Inc. v. Perrigo Co., 616 F.3d 1283, 

1290 (Fed. Cir. 2010) (“A claim construction that excludes 

the preferred embodiment ‘is rarely, if ever, correct and 

would require highly persuasive evidentiary support.’ ” 

(citation omitted)).

Further undermining the construction of “customary 

in a host device” as “normally found in the chassis of most 

commercially available computers” is the fact that the 

written description does not equate “host device” with 

“computer.” To the contrary, the description uses the 

words “host device,” “host systems,” “computer,” and 

“computer systems” more or less interchangeably. See, 

e.g., ’399 patent, col. 1, lines 20–21 (“host devices or 

computer systems are attached by means of an interface 

to a device”); id., lines 49–50 (describing an “electronic 

measuring device . . . attached to a computer system”); id.

col. 2, lines 1–7 (referring to “host systems” and “computer systems”); id. col. 4, line 60, to col. 5, line 32 (alternating between “host device,” “host systems,” “computer 

system,” and “computer”); id. col. 8, lines 1–22 (similar). 

Even if we were to conclude that the phrase “customary 

in” conveys a physical location, therefore, the district 

Case: 14-1110 Document: 121-2 Page: 27 Filed: 02/02/2015
28 PAPST LICENSING v. FUJIFILM CORPORATION

court was wrong to conclude that the physical location 

must be inside a computer chassis. See Pickholtz v. 

Rainbow Techs., Inc., 284 F.3d 1365, 1373–74 (Fed. Cir. 

2002) (construing “located in the computer” to mean 

“located in the CPU, main memory, the CPU or main 

memory circuit boards, or qualifying peripherals” based 

on the written description’s repeated use of “computer” 

and “computer system” interchangeably).

CONCLUSION

For the foregoing reasons, we vacate the district 

court’s entry of final judgment and remand for further 

proceedings consistent with this opinion.

Costs are awarded to Papst.

VACATED AND REMANDED

Case: 14-1110 Document: 121-2 Page: 28 Filed: 02/02/2015