It's been a bitter out-of-court battle, and now it has landed in the courtroom. Oracle is suing Google for patent and copyright infringement surrounding the Android operating system.

Oracle argued that Android uses Java technologies to compete with Java, which is itself a competitive mobile Relevant Products/Services operating system. Google did not immediately respond to Oracle's allegations. But in October, Google emerged with a response that Google's platform, including its Dalvik virtual machine, does not violate Oracle's intellectual property.

Google has called the suit an "attack Relevant Products/Services on both Google and the open-source Java community," and has argued that Oracle's claims are "baseless."

Google said although software Relevant Products/Services applications for the Android platform may be written in the Java programming language, the Dalvik byte code is distinct and different from Java byte code. The Dalvik VM is not a Java VM.

But Oracle maintains that "in developing Android, Google knowingly, directly and repeatedly infringed on Oracle's Java-related intellectual property."

Call it a battle of the tech titans -- and plenty is at stake as the arguments opened Monday in U.S. District Court in San Francisco. Oracle first filed the lawsuit in August 2010 and the case has been trying to make its way to trial since last October.

Google's Thin Patent Portfolio

We called Rob Enderle, principal analyst at the Enderle Group, to get his views on what to expect in the Oracle vs. Google patent trial. He told us the stakes are high for Google and Android.

"Oracle is going to try to make Google pay for [Oracle's] Sun acquisition, which would be kind of ironic. That implies that if Google had bought Sun, shut it down and taken it for its patents it would have been a good deal," Enderle said.

"That's something I don't think Google realized. Google is slowly coming around to the idea that it needs some sort of patent defense Relevant Products/Services."

Oracle spent $7.4 billion to acquire Sun in 2010. Google has since been working to build a patent portfolio, bidding $900 million for Nortel Network's patent portfolio -- and losing -- and later buying more than 200 patents from IBM. Google also spent $12.5 billion to buy Motorola, which beefed up its patent portfolio.

A Personal Battle?

"Part of what makes this case big and expensive is that [late Apple CEO] Steve Jobs was one of [Oracle CEO] Larry Ellison's closest friends. Clearly Jobs took what he saw as Google's theft of his intellectual property rather personally," Enderle said.

"Jobs wanted Google punished for what it did, and part of Larry's motivation isn't just financial. Part of it is now doing a departed friend a service."

As Enderle sees it, Oracle is likely willing to spend more to litigate the Google patent case than it may a typical patent suit -- even if it it doesn't look like it is going to pan out. That said, Oracle has historically had a strong track record in the courtroom. And that's where the Google case is likely to get decided.

"I don't see the parties settling. This is one that's going to go through the courts. That also suggests there will be appeals on both sides," Enderle said. "When you get emotions involved it gets very expensive. They've already had a number of attempts to settle, but the two parties are so far apart that they may as well be in different galaxies. This is not going to settle out of court. This is going to go to the distance."