Vanessa Blum writes for The Recorder, an American Lawyer affiliate.

The calvary has arrived in the Apple-Samsung patent fight.

On Monday a coalition of technology companies led by Android developer Google Inc. publicly stepped up to back Samsung Electronics Co. in its appellate battle with Apple Inc. over injunctions.

In an amici curiae brief comparing Apple’s bid for a sales ban to "highway robbery," the tech firms are urging the U.S. Court of Appeals for the Federal Circuit to uphold a lower court decision denying permanent injunctions against Samsung phones and tablets, which use Google’s Android software.

In Apple v. Samsung, a federal jury in San Jose awarded Apple $1.05 billion after a trial last year, concluding an array of Samsung products violated Apple’s patents and trade dress. However, U.S. District Judge Lucy Koh refused to grant injunctions, finding Apple had not shown a strong enough link between the infringement and consumer demand for Samsung devices. (Koh also slashed the jury’s damage award by more than one-third and ordered a new damages trial.)

Siding with Samsung as amici with Google are cloud computing firm Rackspace and software developers Red Hat Inc., SAP America Inc. and HTC Corp., which developed the first Android smartphone and settled patent litigation against Apple last year.

The group, represented by lawyers in the New York and Palo Alto offices of White & Case, contends Koh’s decision should stand and that rewarding Apple’s litigation strategy with injunctions would stifle competition and innovation.

"Awarding injunctive relief in this circumstance would severely penalize defendants," wrote White & Case partners Christopher Glancy, Kevin McGann and Warren Heit. "The owner of a trivial patent has no reasonable expectation of more than trivial compensation."

McGann referred questions to Google, which did not respond to a request for comment.

The standard for an injunction based on patent infringement is one of the key legal questions to develop from the smartphone war between rivals Apple and Samsung. In March mobile phone maker Nokia Corp., which fought its own patent battle with Apple from 2009 to 2011, filed an amicus brief supporting Apple’s position in Apple v. Samsung, arguing that Koh’s order had set too high a bar for patent holders to obtain injunctions.

By weighing in on the other side of the dispute, Google is making an official court appearance in a case that implicates its Android technology and where it has already been seen as influential. Samsung’s law firm, Quinn Emanuel Urquhart & Sullivan, previously represented Google in patent litigation and has defended other Android handset makers in suits filed by Apple and Microsoft Corp. Apple is represented by Morrison & Foerster and Wilmer Cutler Pickering Hale and Dorr.

Samsung filed an appellate brief last week defending Koh’s ruling on injunctions, which hewed closely to the U.S. Court of Appeals for the Federal Circuit’s 2012 decision in separate litigation between Apple and Samsung. In that case, dubbed Apple II, the Federal Circuit required that patent holders seeking injunctions show a "causal nexus" or a direct link between lost market share and a specific infringing feature of a competitor’s product.

Samsung’s legal allies also embrace the logic of Apple II in their amici brief, stating that "courts cannot simply assume that a patent holder’s alleged irreparable harm (here, loss of market share) stems from infringement instead of from lawful competition."

But with the law still evolving, the group also points to authorities of a less precedential sort, including articles by Mark Lemley, director of Stanford Law School’s Program in Law, Science and Technology, and Carl Shapiro, a UC-Berkeley economics professor. Lemley, a partner at the San Francisco patent boutique Durie Tangri, has represented Google in unrelated litigation. Samsung also referenced several news articles and editorials in its brief, while Apple cited one law review article.

Peder Batalden, a partner at the Los Angeles appellate boutique Horvitz & Levy, said that could be an indication there are a dearth of cases to back Samsung’s position.

"Generally I don’t think you’d cite an article if you had a more traditional authority," he said.

However, referencing articles and commentary can also be a strategy for pointing the court to the larger implications of a case, Batalden said.

"They can emphasize to a court how important an issue is or how many people it affects or simply the existence of controversies," he said.

It’s clear which side of the controversy Lemley is on. In an email, Lemley said the Federal Circuit’s ruling on injunctive relief could make sales bans rare in "complex, multicomponent industries like smartphones."

"As I have suggested in my academic work, that is as it should be," he added. "We don’t want the tail of a minor patent to wag the dog, whether that patent is owned by a troll or a competitor."