The Supreme Court has refused to intervene in a patent fight over a way to cure tobacco that may make it less carcinogenic.

The high court on Monday refused to hear an appeal from R.J. Reynolds Tobacco Co. The Winton-Salem, N.C.-based company is being sued by Star Scientific Inc.

Star Scientific said R.J. Reynolds infringed on its patents on a way to cure tobacco that minimizes the formation of tobacco-specific nitrosamines or TSNA, which may be carcinogenic.

A trial court ruled the patents are unenforceable because the inventor kept from the Patent and Trademark Office key information, including that low-TSNA tobacco already had been grown in the U.S.

The U.S. Court of Appeals for the Federal Circuit overturned that decision, saying a judge cannot throw out a patent without clear and convincing evidence that a deception was intentional.