The US Patent and Trademark Office has rejected 17 of 21 claims included in one of the patents that Oracle is asserting against Google over its use of Java in the Android operating system.
Google requested a re-examination of patent number 6,192,476 in March. The patent covers a method of detecting a request for access and then checking to see whether the request is authorised to be carried out, according to a tiered access system.
Following the re-examination, the US Patent and Trademark Office (USPTO) dismissed 17 of Oracle's claims asserted in the patent citing prior art, according to Groklaw on Wednesday. Google has a number of other re-examination requests outstanding in the case.
Prior art covers any information that has been publicly disclosed in any form before the date that the patent was granted.
"While Oracle has asserted seven different patents in its claims against Google, if this re-examination is exemplary of what Oracle can expect in each of the other re-examinations, Oracle will have a hard time finding claims that it can successfully assert against Google, and there lies Oracle's conundrum," Groklaw wrote.
In May, US District Judge William Alsup told Oracle to slim down the number of Android patent claims against Google to a "triable number". There were 132 claims spread across seven patents.
The difficulty now, according to Groklaw, is deciding which claims to omit.
"If Oracle narrows the claims it asserts in order to satisfy the court, it may find it has asserted a claim the USPTO is now rejecting. Wait for the re-examinations to run their course, and Oracle may find it has nothing left to assert," Groklaw wrote.