HP is suing its recently fired president and CEO, Mark Hurd, for taking a job at Oracle, and that’s a move that Larry Ellison called “vindictive.” Mr. Hurd was hired to serve as Oracle’s president and as a member on the company’s Board of Directors.

“Oracle has long viewed HP as an important partner,” Mr. Ellison, Oracle’s CEO, said in a statement. “By filing this vindictive lawsuit against Oracle and Mark Hurd, the HP board is acting with utter disregard for that partnership, our joint customers, and their own shareholders and employees.”

Mr. Hurd lost his job at HP in early August over sexual harassment claims from a former contractor. A company investigation concluded that Mr. Hurd didn’t violate sexual harassment policies, but said violated HP’s rules pertaining to business conduct.

According to HP, Mr. Hurd violated the terms of his contract by taking the job at Oracle, and they allege his position ensures he’ll divulge company secrets.

HP’s decision to sue Mr. Hurd seems to have Mr. Ellison fighting mad, and he went so far as to toss a very thinly veiled threat HP’s way. “The HP Board is making it virtually impossible for Oracle and HP to continue to cooperate and work together in the IT marketplace,” he said.