The federal judge overseeing the Java patent litigation between Oracle and Google has said it might be necessary to delay a trial until US authorities finish re-examining a number of Oracle's patents, a process that could take years.

Oracle sued Google in August, alleging that its Android mobile OS infringes on seven of Oracle's Java patents. Google has denied any wrongdoing.

"The larger the number of patents and patent claims at trial, the greater will be the burden on the jury's ability to comprehend and to reach a just and correct verdict," U.S. District court Judge William Alsup wrote in a filing this week. "The larger the number of patents and patent claims asserted, moreover, the more practical it will then seem to simply stay this case and see which claims survive PTO re-examination."

Alsup had previously asked both Oracle and Google to reduce the number of claims each is making, in order to resolve the case more quickly.