Last Month at the Federal Circuit
Last Month at the Federal Circuit

November 2012

Causal Nexus Test for Irreparable Harm Requires Plaintiff to Prove That Allegedly Infringing Features Affirmatively Drive Consumer Demand for the Accused Product


Judges:  Prost (author), Moore, Reyna
[Appealed from N.D. Cal., Judge Koh]

In Apple Inc. v. Samsung Electronics Co., No. 12-1507 (Fed. Cir. Oct. 11, 2012), the Federal Circuit held that the district court abused its discretion by entering a preliminary injunction and that it erroneously construed the terms of an asserted claim.

Apple Inc. (“Apple”) filed suit against Samsung Electronics Company, Ltd., Samsung Electronics America, Inc., and Samsung Telecommunications America, LLC (collectively “Samsung”), alleging that Samsung’s Galaxy Nexus smartphone infringes eight patents.  The only patent-at-issue in this appeal, however, was U.S. Patent No. 8,086,604 (“the ’604 patent”).  Claim 6 of the ’604 patent is directed to an apparatus for “unified search” that employs heuristic modules to search multiple data storage locations.  Simply put, the claimed device can access information stored in more than one location through a single interface by using a particular search algorithm.  When a user inputs a search query to the unified search interface, the claimed device submits it to different heuristic modules, each confined to a predetermined search area.  The device then compiles the results, optionally filters them, and displays them to the user.  Apple’s search assistant, Siri, for example, employs unified searching. 

Apple alleged that the Quick Search Box feature implemented in Samsung’s Galaxy Nexus (through its use of Google’s open-source Android platform) infringes claim 6.  Relying on four of the eight patents asserted in its complaint, Apple further moved for a preliminary injunction, requesting an immediate halt to sales of the Galaxy Nexus.  Ultimately, the district court issued an injunction based solely on Samsung’s alleged infringement of the ’604 patent.  Samsung moved to stay the injunction pending appeal, but the district court refused.  Samsung appealed immediately.  Not only did the Federal Circuit grant Samsung a temporary stay of the injunction until resolution of this interlocutory appeal, but it also expedited the proceedings.


“The causal nexus requirement is not satisfied simply because removing an allegedly infringing component would leave a particular feature, application, or device less valued or inoperable.”  Slip op. at 10.

Reviewing the district court’s decision de novo, the Federal Circuit first laid out the traditional four factors that a court must weigh when determining whether to grant a preliminary injunction:  (1) whether the plaintiff is likely to succeed on the merits; (2) whether the plaintiff is likely to suffer irreparable harm without such relief; (3) whether the balance of equities favors the plaintiff; and (4) whether an injunction serves the public interest.  This appeal focused primarily on what constitutes irreparable harm.  Although prior Federal Circuit case law offers little guidance in that regard, it does state that when an accused product incorporates many features—only a small minority of which may infringe—irreparable harm does not alone justify injunctive relief.  Rather, such circumstances further require that the harm bears a “sufficiently strong causal nexus” to the alleged infringement.  Slip op. at 6.

Here, the Court pointed out that the irreparable harm and causal nexus inquiries are inextricably related, i.e., part of the same inquiry.  “The relevant question is not whether there is some causal relationship between the asserted injury and the infringing conduct, but to what extent the harm resulting from selling the accused product can be ascribed to the infringement.”  Id. at 7-8.  In this case, the Court clarified that merely establishing a connection between the alleged harm and infringement does not suffice; rather, the allegedly infringing feature must affirmatively drive consumer demand.  The district court, on the other hand, erroneously believed that a sufficient nexus also exists when the patented feature’s absence would suppress consumer demand or render the accused product inoperable.

Because Apple’s evidence of causal nexus was limited, the Federal Circuit held that the district court abused its discretion in granting a preliminary injunction.  Apple offered no direct evidence, only minimal circumstantial evidence, mostly relating to the popularity of its Siri application.  The panel noted, however, that Samsung’s Galaxy Nexus does not contain anything equivalent to Siri.  Moreover, the unified search feature of Siri comprises only a small portion of its functionality.  Thus, the mere fact that Samsung’s Quick Search Box also incorporates unified searching does not itself establish a sufficient causal nexus.  Nor do any of the other three documents relied on by Apple, which consist primarily of blogger opinion and Android information provided to developers.

Having reversed the district court’s injunction order, the Federal Circuit then addressed part of the district court’s claim construction “in the interest of judicial economy.”  Id. at 12.  Claim 6 recites “a plurality of heuristic modules . . . , wherein:  each heuristic module corresponds to a respective area of search and employs a different, predetermined heuristic algorithm.”  Id. at 3-4 (citation omitted).  Apple argued that this language covers a device employing at least two modules using different heuristic algorithms, even if it also employs other heuristic modules not using unique algorithms.  Samsung, however, argued that claim 6 requires that every heuristic module use a unique heuristic algorithm.  The district court agreed with Apple.

The Federal Circuit concluded that the district court’s reading contravenes the plain language of claim 6.  It reasoned that “each” does not modify “plurality of heuristic modules” because the word “each” resides inside the “wherein” clause, not before “plurality of heuristic modules.”  The district court erred by simply relying on the Federal Circuit’s construction of similar claim language in an earlier case.  By doing so, however, it actually “eliminated the very distinction that [the Federal Circuit] deemed material in [that case],” a mistake that the panel characterized as “at best—incorrect.”  Id. at 15.  The panel found further support for its claim construction in the specification and prosecution history, disagreeing with the district court’s interpretation of that same evidence.

The Federal Circuit remanded the case to the district court for further proceedings.

J. Preston Long is a Law Clerk at Finnegan.