The relationship was with a woman who still works at Intel and started about a decade ago, sources told the Journal. She was reportedly a middle manager at the start of the relationship and didn't work closely with Krzanich.
Krzanich, whose wife Brandee previously worked at Intel as a process engineer, became CEO in 2013.
The affair reportedly ended in 2013, before he became CEO. The policy he's accused of violating, which prohibits managers from having sexual and romantic relationships with direct and indirect reports, was put in place in 2011.
Before the policy was implemented, Intel had multiple highly-visible office relationships. Krzanich's predecessor, the late Paul Otellini, met his wife Sandy at the company. She was a lawyer at Intel until 1995.
Krzanich's resignation follows months of high-profile resignations and dismissals across industries as the #MeToo movement sheds light on inappropriate workplace behavior exhibited by men in power.
Though the events are reportedly years old, Krzanich's resignation was triggered when an employee mentioned the past relationship to a colleague, who then reported it to Intel's general counsel on June 14, according to the Journal.
Outside of the affair, Krzanich's last year as CEO was marred by the Spectre and Meltdown chip security flaw as well as his $24 million (R330 million) stock sell off before Intel publicly disclosed the flaw.
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