An attorney for US meat processor Tyson Foods has told an appeals court panel that a federal judge ruled correctly when he found in favour of the company in a cattle price-fixing lawsuit.

Carter Phillips backed Judge Lyle Strom's decision to reverse a jury verdict against Tyson in April by ruling the company did not violate the law through its supply agreements with independent cattle producers.

The plaintiffs, who claim cattle marketing agreements amount to price fixing and sued Tyson Fresh Meats - known as IBP when the suit was filed - in 1996, are appealing Strom's decision in the 11th Circuit Court of Appeals.

Tyson said it does not know when the three-member appeals court panel will release its ruling on the plaintiffs' appeal. Such decisions typically take three to six months but can take longer.