Oracle chief executive Larry Ellison says Hewlett-Packard's board was wrong to force the resignation of company chief Mark Hurd.
"The HP board just made the worst personnel decision since the idiots on the Apple board fired Steve Jobs many years ago," he said in a letter to the New York Times.
Hurd resigned after an internal investigation found he had made inaccurate expense claims and concealed a relationship with events contractor Jodie Fisher.
But investigators said Hurd was not guilty of sexual harassment, as alleged by Fisher, who settled her claim out of court.
"In losing Mark Hurd, the HP board failed to act in the best interest of HP's employees, shareholders, customers and partners," Ellison said in the letter.
"The HP board admits that it fully investigated the sexual harassment claims against Mark and found them to be utterly false," he said.
Apple dismissed Jobs in 1985 after he clashed with CEO John Sculley, but he returned 12 years later to lead a successful comeback for the company,
"That decision nearly destroyed Apple and would have if Steve hadn't come back and saved them," Ellison said.