Apple narrowed the potential damages Qualcomm can seek over alleged patent infringement before the two square off at a trial scheduled to start next month in San Diego.

A federal judge on Tuesday granted Apple’s request to preclude Qualcomm from seeking financial compensation for infringement before the lawsuit was filed in 2017. The judge also ruled that Apple isn’t infringing one of the several patents that Qualcomm says are at stake in the litigation.

Qualcomm accused Apple of infringing patents related to technology for graphics processing and energy efficiency in mobile phones. They are distinct from the so-called standard essential patents for wireless communications that are at issue in Apple’s separate antitrust allegations against the chipmaker. The case is one of a number of patent disputes in the sprawling global fight between the two technology giants that has given each side isolated wins.

Qualcomm is asserting that Apple infringed non-standard non-essential patents to show the overall value of its collection of inventions. The company charges licensees fees based on the selling price of a phone and says those fees fund research that helps the whole industry. Opponents argue that Qualcomm’s contributions to the industry are more limited and it has used unfair practices to force them to pay inflated fees.

Apple’s Asian manufacturers, through whom Qualcomm was paid royalties for its patented technology used in iPhones and iPads, stopped paying shortly after Apple sued Qualcomm in January 2017 for improperly using its market position to demand excessive royalties. Tuesday’s ruling precludes Qualcomm from seeking damages for patent infringements for the months from when the payments were halted to when it filed its lawsuit.

U.S. District Judge Dana Sabraw sided with Qualcomm on the fact that Apple can’t argue before the jury that a Qualcomm patent for a “flashless boot” technology was already publicly disclosed in a manual for Blackfin processors. That patent enables mobile phones to connect to the internet immediately upon startup.