Two longtime IBM Corp. executives are retiring, prompting the technology company to reshuffle its top ranks.

William Zeitler, 60, who has been running IBM’s hardware group, will hand the division to Robert Moffat, who most recently has been in charge of IBM’s supply chain. Zeitler plans to retire Aug. 1 after 39 years at IBM.

Nick Donofrio, 62, who had been executive vice president for innovation and technology, is retiring as of Oct. 1. He has spent 44 years in the company, beginning when he was still a college student.

Donofrio’s position won’t be filled. Instead IBM executives who had been reporting to him, including research head John Kelly, will now report directly to IBM’s chairman and chief executive, Samuel Palmisano.