The Associated PressA federal jury ruled on Tuesday that RJ Reynolds Tobacco Co. did not infringe on two patents claimed by Star Scientific for a tobacco-curing method. Star Scientific shares lost nearly 80 percent of their value in late trading. Both companies said the jury in Baltimore found that the patents were invalid. Star Scientific sued RJ Reynolds, a unit of North Carolina-based Reynolds American, in 2001 over a method of treating tobacco to prevent the formation of tobacco-specific nitrosamines. In March, the Supreme Court refused to hear the case, clearing the way for the trial that led to Tuesday's verdict in U.S. District Court in the Northern Division of Maryland. Petersburg, Va.-based Star Scientific said it would ask the district court judge to rule in its favor as a matter of law or for a new trial. Failing that, it said it would file a notice that it intends to appeal to the U.S. Court of Appeals. Shares of Star Scientific Inc. closed at $4.21 before the verdict, but fell $3.33, or 79 percent, to 87 cents in late trading. Reynolds American shares fell 22 cents to close at $36.33, then rose 71 cents to $37.04 after the verdict in after-hours trading.