Lawyers for Oracle and Google came before Judge William Alsup at the U.S. District Court in San Francisco on Wednesday for a so-called claims construction hearing, where the two sides argue over how language in the patents should be interpreted.

Scott Weingaertner, an attorney for Google, told the judge towards the end of the hearing that the U.S. Patent and Trademark Office has agreed to reexamine Oracle's Java patents.

"The patent office has granted reexamine requests on all the patents in this case," Weingaertner said.

Alsup asked when that happened. "It happened as recently as yesterday with one of them. It's been happening over the last few weeks," Weingaertner said

It's not uncommon for defendants to ask for patents in a case to be reexamined. The patent office could potentially invalidate claims in the patents or narrow their scope, or it could choose to take no action at all. Seeking a reexamination is sometimes used simply as a delaying tactic.