Brief of the day: Apple on Google as a ‘friend of the court’

FORTUNE — Following its $1.05 billion patent infringement victory last summer, Apple (AAPL) appealed the district court judge’s decision not to ban the sale of the Samsung devices that the jury determined had infringed multiple Apple patents.

Google (GOOG) and several other companies now want to file an amicus curiae (“friend of the court”) brief to the appeals court in support of Samsung.

As Apple points out in its reply, filed Tuesday, Google is hardly a disinterested party:

The lead party on the brief, Google, Inc., admittedly has a direct interest in the outcome of this appeal. As the motion explains, Google is the developer of the Android operating system running on the Samsung smartphones that Apple seeks to enjoin in this case. That interest conflicts with the traditional role of an amicus as “an impartial friend of the court — not an adversary party in interest in the litigation.” United States v. Michigan, 940 F.2d 143, 165 (6th Cir. 1991) (emphasis in original)

Indeed, when amici have such a stake in the outcome of the case, courts have denied them leave to participate to prevent “an end run around court-imposed limitations on the length of parties’ briefs.”

See: Apple Opposition to Google et al. Amicus Curiae Brief in Samsung Case.

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