Oracle is suing Google for billions of dollars and on Thursday Larry Page, the CEO of Google parent company Alphabet, was called to the stand by Oracle’s lawyers to testify.

Oracle’s lawyers asked him about the revenue that Google generates from its Android software, which is something Google doesn’t publicly discuss.

Oracle’s expert witness had previously testified that Google has generated $42.3 billion from Android, mostly through advertising.

The lawyer showed Page a document presented to Google’s board of directors about Android saying, “Our application and advertising services helped build Android into $43B / year ecosystem,” according to the live coverage of the trial relayed on Twitter by several reporters and observers at court on Thursday.

But Page balked at that document.

“I don’t think those revenues are Google’s revenues,” he told the court, according to tweets from Sarah Jeong, who is covering the trial for Motherboard.

Page said he thought the number referred to how much the entire ecosystem has made on Android, including carriers and others, not just Google.

Oracle is suing Google for billions of dollars, alleging that Google owes it a lot of money in royalties and damages for copying certain bits of software from a programming language called Java to when Google created Android.

Oracle now owns Java, acquired when it bought the company that created it in 2010, Sun Microsystems. At issue are bits of computer code called application programming interfaces or APIs. These let two apps work together and share data.

Page didn’t play into Oracle’s hands

Page also got in a bunch of other jabs on the stand:

When asked why Google acquired the company that had initially created Android, Page took a shot at Java, the programming language owned by Oracle at the heart of this trial.

“I was frustrated with the state of phones at the time… many of which were running Java,” he replied, according to tweets from EFF activist Parker Higgins.

In a line of questioning about how if he knew that Google did not licence these APIs from Sun (yes, he did know that), Page also pushed back, “I don’t agree we copied code,” reports Motherboard’s Jeong.

Page said he thought it was industry practice to take API headers and re implement them. In other words, he thought the bits that Android copied were not creative bits of code, but just some programming structure that everyone freely grabbed from other programs.

This is the third phase of a long-running trial. In the previous go-round, Oracle showed 9 lines of code, now infamous, that were duplicated from Java. Android includes millions of lines of code. By the end of the trial the disputed code included 37 APIs, about 11,000 lines of code.

Google argued that APIs shouldn’t be subject to copyright law. A jury agreed (and so did Europe, which ruled in 2012 that APIs aren’t subject to copyright law). But a US appellate court overturned the decision and declared a victory for Oracle.

This trial will determine how much money, if any, Google owes Oracle. Google is now arguing that its use of these APIs fall within fair use. And the whole software industry is holding its breath. Many feel that if APIs are subject to copyright law, that could unleash lawsuit Armageddon in the software industry.

So Page didn’t give the Oracle lawyers any of the admissions they were looking for.

Much of this case rests on emails from Andy Rubin, chief architect and former head of Android for Google, who sent emails saying he thought the bits of code were indeed copyrighted, owned by Sun and needed licenses.

In fact, the best dig the Oracle lawyer got on Page was when he presented Page with another email from Rubin that warned if Google proceeded with Android without a Java licence, the company could “make some enemies along the away.”

The trial ends on Thursday.

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