HP's former CEO Mark Hurd was forced out in the wake of a scandal which may or may not have involved a romantic relationship with a contractor. What it did involve was filing bogus expense reports. Hurd left, and got a pretty smashing severance package. HP may have been planning to let things lie, but with the news that Hurd intends to join Oracle, HP is willing to go to court .
HP claims that Hurd signed agreements to protect HP's trade secrets, and his work at Oracle would break those agreements. HP's complaint reads in part, "In his new positions, Hurd will be in a situation in which he cannot perform his duties for Oracle without necessarily using and disclosing HP’s trade secrets and confidential information to others."
This story is still developing, but it looks like it won't be smooth sailing for Mark Hurd after all. It is common for companies to enforce so called "non-compete" agreements when high-level executives leave. Check out the source link to download the full documents if you fancy some legal reading.