Mobile chip maker Qualcomm Technologies Inc. has had a rough ride so far this year, and it’s not getting any better.

It has had to fend off a lawsuit from one of its largest customers Apple Inc. over accusations of unfair licensing practices. In addition, the company was also accused in January of using anti-competitive tactics by the Federal Trade Commission. Now, on that case, two of Qualcomm’s main rivals, Intel Corp. and Samsung Electronics Co. Ltd., have chimed in on the side of the FTC.

The FTC’s case is that Qualcomm uses standards-essential patents it owns to force smartphone makers and other firms in the mobile semiconductor industry to pay higher royalties and license payments. But the FTC says that doing so is a violation of its rules on its “fair, reasonable and non-discriminatory” licensing terms.

On Friday, both Intel and Samsung filed amicus briefs with U.S. courts that support the FTC’s lawsuit and reject Qualcomm’s bid to have the case dismissed, Bloomberg reported. Both companies alleged in their statements that Qualcomm abuses its patents in order to retain its position as the No. 1 player in the mobile chip industry.

“Qualcomm has maintained an interlocking web of abusive patent and commercial practices that subverts competition on the merits,” Intel wrote in its complaint.

Samsung also complained that because Qualcomm refuses to offer the necessary licenses, its Exynos chips aren’t available to other companies. The company, which is the world’s largest smartphone maker, uses a mixture of suppliers, including itself and Qualcomm, for crucial components used in its handsets.

“Despite having requested a license from Qualcomm, Samsung cannot sell licensed Exynos chipsets to non-Samsung entities because Qualcomm has refused to license Samsung to make and sell licensed chipsets,” the company said in its filing.

On the same day, the FTC also made representations to the judge, urging him to reject Qualcomm’s request for the case against it to be dismissed. The FTC said in a filing that its allegations “present a forceful antitrust case,” and that the case should proceed. It came after Qualcomm’s General Counsel Dan Rosenberg said last month the FTC’s allegations are riddled with “fallacies and failures.”

“The Federal Trade Commission’s latest submission to the court does nothing to cure the fundamental flaws in its complaint against Qualcomm: no coherent theory of competitive harm and no allegations of the type of conduct that the antitrust laws are designed to address,” Qualcomm said in a statement Friday. “The complaint therefore should be dismissed.”

Qualcomm’s trial is set to begin on June 15, so it may not be long before there’s a resolution.

Image: Ricardo Ulke Acosta/Flickr.com