As promised, Oracle just filed its appeal in its massive case against Google

If you thought the loss Oracle suffered in May in its ongoing lawsuit against Google over Android was the end, think again.

As promised, Oracle is appealing the case, and filed its appeal today.

The two tech giants have been battling it out for years in two separate court cases over whether Google must pay Oracle billions of dollars for bits of code copied from Java (a programming language Oracle owns) and used in Android (the language Google controls).

At issue were bits of code called application programming interfaces (APIs), the technology that allows different computer programs to talk to each other.

While there's been back and forth over the years, with one side winning or losing various stages of the fight, the upshot is, Google has yet to be found liable for paying Oracle for Java, much less the massive, multi-billion dollar fine Oracle dreams of.

Chilling effect

In May, the two companies were in court arguing over what amount, if anything, Google owes after an earlier trial found that Google did in fact copy some of the Java code.

Google argued that the copying fell within the "fair use" provision of copyright law, meaning Google was free to use it. A jury of 10 unanimously agreed with Google. Oracle vowed to appeal and here we are.

In the appeal filing, seen by Business Insider, Oracle argues that the jury in May didn't get to hear all of the facts it wanted to share. Those facts included all the ways it believes Android harms Java, including how Android might one day usurp Java's role in its primary domain, as a language used to create apps and Web apps for PCs.

Oracle's lawyers argue in the appeal filing:

"Google started trial knowing a fact it kept secret from everyone else: It was days away from announcing that 'the full functionality of Android would soon be working on desktops and laptops, not just on smartphones and tablets.'"

Many in the tech industry have been watching this case closely. Critics argue that a big fine for Oracle could have a chilling effect on some of the ways that software developers freely use and share code today.

Google is not commenting on the appeal, although it did send Business Insider its original statement when it won the jury case in May.

"[The] verdict that Android makes fair use of Java APIs represents a win for the Android ecosystem, for the Java programming community, and for software developers who rely on open and free programming languages to build innovative consumer products."