Hewlett Packard Enterprise is suing Oracle for $3 billion

Hewlett Packard Enterprise (HPE) and Oracle are heading back to court to determine how much money, if any, Oracle owes HPE over a case it won in 2011.

HPE is going to ask for $3 billion in the breach-of-contract suit.

Since that last trial, Hewlett-Packard has split into two companies, HPE, which makes servers and software for enterprises, and HP Inc., which makes PCs and printers.

HPE is the company pursuing this lawsuit, which came about after Oracle hired Mark Hurd. Hurd was the former CEO of HP. He left HP amid questions involving his expense reports and allegations that he was trying to get one of HP's contract workers to date him.

Oracle had just bought Sun. Larry Ellison was friends and tennis buddies with Hurd and hired Hurd to help him turn Oracle into a hardware company. This meant Oracle was now a competitor to its former partner, HP.

Oracle said it would no longer create versions of Oracle's database for HP's most expensive, most profitable servers, built with a special Intel chip, Itanium. Many of HP's customers had bought that server specifically to run Oracle's database, which needs a powerful server to perform well. That's one of the reasons why Oracle bought hardware company, Sun, to begin with.

(Another reason it bought Sun was to get its hands on Java, Sun's popular web programming language. And that led to Oracle suing Google for billions of dollars, although a jury just sided with Google saying it doesn't owe Oracle any money.)

In the meantime, when Oracle wanted to end support for Itanium, HP sued for breach of contract and won.

Both companies are back in court this week to determine what kind of damages, if any, HPE is owed.

HPE will argue that the confusion over support for its servers cost it $1.7 billion in sales and another $1.3 billion in lost future sales. HP had originally claimed Oracle's decision cost it $4 billion.

Oracle is expected to defend itself vigorously.