David Duffield, who founded PeopleSoft ( PSFT) and then returned to the company as chairman and CEO, has resigned.

The resignation was announced quietly Tuesday in a filing with the Securities and Exchange Commission.

Duffield's departure comes after Oracle's ( ORCL) successful $10.3 billion bid for the Pleasanton, Calif., software maker and is an indication that the combined companies may not have a combined leadership.

Duffield returned to PeopleSoft earlier this year when the board of directors fired CEO Craig Conway, who had bitterly opposed the deal with Oracle and alienated other senior executives with his abrasive, imperious style. At the time, Duffield said he didn't return to sell the company, but after his shareholders voted to accept a $24-a-share offer and Oracle then raised its bid to $26.50 a share, the board of directors surrendered and agreed to merge.

In the same filing, the company disclosed that it is terminating a $125,000-a-month consulting agreement with Aneel Bhusri, the vice chairman of the board. The consulting fee was in addition to Bhusri's regular compensation as a board member.

The filing did not specify the nature of Bhusri's consulting duties, and a company representative could not be reached for comment.

The merger will be completed early next year. So far, other management changes that will affect the two companies have not been announced. Oracle is expected to announce a new organization structure at its analyst meeting on Jan. 26.

Speaking at Oracle's user convention last month, CEO Larry Ellison said layoffs will hit both Oracle and PeopleSoft, but the only specific jobs he mentioned were those at the top of the organization chart. "We won't need two CEOs or two CFOs," he said.