In Hill-Rom Services, Inc. v. Stryker Corp., No. 13-1450 (Fed. Cir. June 27, 2014), the Federal Circuit reversed the district court's SJ of noninfringement, finding that it was based on several erroneous claim constructions.

Hill-Rom Services, Inc., Hill-Rom Company, Inc., and Hill-Rom Manufacturing, Inc. (collectively "Hill-Rom") own three patents related to remote hospital bed monitoring—U.S. Patent Nos. 5,699,038 ("the '038 patent"); 6,147,592; and 7,538,659 (collectively "the patents-in-suit").  All three patents-in-suit share a common specification, which discloses hospital beds equipped with sensors that monitor parameters such as the patient's presence and the height of the bed.  In the patented system, an interface board processes the monitored signals to create bed condition messages, and sends the bed condition messages over a datalink to a remote location.  In some cases, the messages may also include message validation information.

Hill-Rom brought suit against Stryker Corporation and Stryker Sales Corporation (collectively "Stryker") for infringing the patents-in-suit.  The parties stipulated to noninfringement based on the district court's construction of four claim terms—"datalink," "interface board including a processor," "message validation information," and "bed condition message."  Hill-Rom appealed the SJ of noninfringement.

"There are no magic words that must be used, but to deviate from the plain and ordinary meaning of a claim term to one of skill in the art, the patentee must, with some language, indicate a clear intent to do so in the patent. And there is no such language here."  Slip op. at 7. [S]tatements made during prosecution of a later, unrelated patent cannot form the basis for judicial estoppel."   Id. at 22.

On appeal, the Federal Circuit held that the district court's judgment was premised on erroneous claim constructions.  First, the Court found that the district court's construction of "datalink"—"a cable connected to the bed that carries data"—was overly narrow because it did not include wireless datalinks.  Slip op. at 4 (quoting Hill-Rom Servs., Inc. v. Stryker Corp., No. 1:11-CV-1120, 2013 WL 364568, at *8 (S.D. Ind. Jan. 30, 2013)).  The Court found that references to "datalink 39," "serial datalink 39," and "cable 39" in the specification did not limit the "datalink" to a cable because those terms were used when referring to the preferred embodiment, and never when referring to the invention as a whole.  Id. at 7.  Likewise, a patent examiner's remarks during prosecution of a later unrelated patent—that the specification did not teach a wireless receiver—also failed to convince the Court that the "datalink" should be limited to a wired connection.  In the Court's view, this statement was directed to the embodiments of the patents-in-suit, and simply acknowledged that they did not disclose an embodiment using a wireless receiver.  But the Court noted that patents are not required to teach what is well known in the art.  Thus, because wireless datalinks were known at the time the patents-in-suit were filed, the term "datalink" should have its ordinary meaning, even if the patents-in-suit did not disclose an embodiment with a wireless datalink.  Relying in part on testimony from Hill-Rom's expert, the Court found that the plain and ordinary meaning of a "datalink" at the time the patents-in-suit were filed would be "a link that carries data in a wired or wireless fashion."  Id. at 11.

Second, the Court found that the district court's construction of the term "interface board including a processor" was incorrect because it required the interface board to both send and receive messages. Thus, the Court held that the "interface board including a processor" is "the interface between the bed components and the off-bed components that processes the bed condition input signals."  Id. at 12.  The Court noted that the ordinary meaning of "interface" does not require two-way communication, and the independent claims of the '038 patent only require sending messages from the interface board to a remote location.  The Court also found that the district court's construction would improperly require the interface board to send messages through a "wall interface unit."  The Court noted that the claims do not require a wall interface unit, and that the specification discloses at least one embodiment where messages are not sent through a wall interface unit.

Third, the Court found that "message validation information" was not limited to a single data field, as the district court's construction would have required.  Although the specification disclosed embodiments that used a single verification field, the Court found nothing in the specification suggesting that using a single field is important or valuable to the invention.  The Court also noted that the claimed validation does not have to perform flawlessly to meet the "message validation information" limitation.  The specification discloses an embodiment where a CHECKSUM field is used for validation and, as the specification notes, a CHECKSUM implementation may fail to catch an error in some cases.

Finally, contrary to the district court's construction, the Federal Circuit construed the term "bed condition message," consistent with its plain meaning, as "a message that indicates the status of a monitored bed."  Id. at 19.  The Court found that the district court's additional limitation—that the message is "not generated in response to any user request that contains the status of all conditions the bed is capable of monitoring"—was premised on an incorrect application of judicial estoppel, based on statements made by Hill-Rom during prosecution of a later, unrelated patent.  Id. at 19-21 (citation omitted).  The Court noted that, under Pfizer, Inc. v. Ranbaxy Laboratories, Inc., 457 F.3d 1284, 1290 (Fed. Cir. 2006), "statements made during prosecution of a later, unrelated patent cannot form the basis for judicial estoppel."  Slip op. at 22.  The Court also explained that judicial estoppel only applies when a party takes a position that is "clearly inconsistent" with its earlier position.  Id.  The Court, however, found that judicial estoppel could not apply since Hill-Rom's earlier statements were ambiguous and not clearly inconsistent with its current position.

Having found that the district court's judgment was based on erroneous claim constructions, the Court reversed the grant of SJ of noninfringement and remanded for further proceedings.

In his dissent, Judge Reyna maintained that the patents-in-suit consistently identified the "datalink" as a physical structure, and did not indicate it included wireless communications.  He also noted that Hill-Rom added wireless communications in a later patent application, which described the patents-in-suit as limited to wired systems.  Judge Reyna stated that the examiner who reviewed this later application did not consider the "datalink" to include wireless technology and that the majority had misconstrued the examiner's remarks.  He disagreed with the majority's construction of "datalink" because it defined the term functionally to include "any and every method of communicating data."  Reyna Dissent at 6.  He also was of the opinion that the term "datalink" would not have been understood to include wireless communications when the patents-in-suit were filed.  Noting that the majority opinion relied on testimony from Hill-Rom's expert for the sole evidence of how the term would have been understood, Judge Reyna found the testimony conclusory and ambiguous.  Thus, Judge Reyna would have limited the claimed "datalink" to a physical connection.

This article previously appeared in Last Month at the Federal Circuit, July 2014.

Judges: Moore (author), Schall, Reyna (dissenting)

[Appealed from S.D. Ind., Judge Magnus-Stinson]

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