Intel CEO Pat Gelsinger has retired, the struggling chipmaker said Monday in a surprise announcement. Two company executives, David Zinsner and Michelle Johnston Holthaus, will act as interim co-CEOs while the company searches for a replacement for Gelsinger, who also stepped down from the company's board.

Intel’s hiring agreement with Gelsinger promised him a severance payment of 18 months of his salary and his annual target bonus if he resigned “for good reason.” In a regulatory filing Tuesday, Intel said that it had agreed to pay him that in connection with his retirement.