David Duffield has resigned as PeopleSoft's CEO and chairman. He lasted less than three months after taking over again as CEO at the company he founded and which is in the process of being acquired by rival Oracle.

According to a filing made by PeopleSoft with the Securities and Exchange Commission (SEC), Duffield resigned on 21 December, only eight days after Oracle announced it had reached an agreement to buy PeopleSoft for about US$10.3 billion [b], ending a nasty takeover battle that lasted for about 18 months.

Duffield is a PeopleSoft founder and had been its chairman since its incorporation in 1987. He was the company's CEO from August 1987 until May 1999, when he was replaced by Craig Conway. Duffield took over again as CEO in October of this year when Conway was fired after the company said the board lost faith in him.

Back in October, Duffield said his re-appointment to the CEO spot was permanent.

Asked whether PeopleSoft had already chosen someone to replace Duffield as CEO and chairman, PeopleSoft spokesman Steve Swasey said the company had no comment beyond what it said in the SEC filing.

The SEC statement only contains one sentence related to Duffield's resignation and offers no details beyond stating that he resigned as CEO, chairman and director.