Google has filed a response to Oracle’s claims that the internet search giant’s Android mobile OS deliberately breached patents owned by Oracle since it acquired Sun.

In the filing, Google claimed that Oracle might have hidden or deleted copyright headers and expressive material to make it look like as if Android’s Dalvik virtual machine was essentially a copy.

Google argued that Dalvik as well as the rest of the Android mobile operating system was created independently.

Google attorney wrote a total of twenty defenses against Oracle’s claims. In one of its defense, the search giant said that any possible violation would have come from third-party code rolled into Android.

Defending the search firm, Google attorney claimed, "Any use in the Android Platform of any protected elements of the works that are the subject of the Asserted Copyrights was made by third parties without the knowledge of Google, and Google is not liable for such use.”

In addition, Oracle was said to have unjustly attempted to include its own patient rights in licenses which otherwise do not have technology it owns.

Oracle had sued Google in August, but the formal trial is scheduled to begin on October 31, 2011.