Intel

(INTC) - Get Report

shares were gaining Wednesday following the news that a federal judge has dismissed a key portion of

Advanced Micro Devices'

(AMD) - Get Report

antitrust suit against the company.

The ruling, which said the court does not have jurisdiction over key claims in AMD's suit, marks a significant victory for Intel as it fends off a legal assault brought by rival chipmaker AMD.

AMD filed the lawsuit in 2005 alleging that Intel has maintained its dominant position in the market for PC microprocessors through a pattern of anticompetitive conduct, including forcing PC makers into exclusive deals with Intel and threatening to retaliate against vendors who used AMD chips.

In a 17-page opinion Tuesday, U.S. District Judge Joseph Farnan endorsed Intel's argument that because AMD's chip-manufacturing facilities are located outside of the U.S., the company is essentially seeking relief for alleged business practices which occurred outside the U.S. and are, thus, outside the court's jurisdiction.

"AMD has not demonstrated that the alleged foreign conduct of Intel has direct, substantial and foreseeable effects in the United States which give rise to the claim," wrote Judge Farnan.

The injuries allegedly suffered by AMD "are foreign injuries that occurred in foreign markets," Judge Farnan wrote.

AMD noted that the rest of its complaint, which includes claims of violations of the Sherman Antitrust Act and California business statutes, remain intact.

"Notwithstanding the judge's ruling today, Intel cannot escape antitrust scrutiny for its conduct ... wherever in the world it occurs," AMD Vice President of Legal Affairs Tom McCoy said in a statement. "As this U.S. litigation is joined by global antitrust investigations, it is clear that Intel cannot escape the consequences of its illegal monopoly abuses."

Shares of Intel were up 3.2%, or 63 cents, at $20.39. AMD shares were up 0.4%, or 10 cents, at $26.09.