Editor's take: CNBC reached out to Microsoft for more information about where specifically the employees slept or how many chose to do so, but came away empty-handed. That's unfortunately, as it'd be interesting to know what sort of accommodations and compensation Microsoft provided to these dedicated employees.

The phrase "essential worker" entered the mainstream lexicon last year during the Covid-19 outbreak, but for some Microsoft employees, it took on a much deeper meaning.

"I heard amazing stories about people actually sleeping in data centers," said Kristen Roby Dimlow, corporate vice president for total rewards, performance and human resources business insights at Microsoft.

"In certain countries there was huge lockdown, and so we would have our own employees choose to sleep in the data center because they were worried they'd get stuck at a roadblock, trying to go home," the executive added.

Microsoft was among the first major tech players to embrace the work from home movement during the early days of the pandemic. Redmond even went so far as to permanently close all of its retail stores last summer, but recently started walking back that move.

Microsoft back in March outlined a hybrid work strategy designed to strike a balance between safety and productivity, allowing those who want to continue to work from home to do so for a while longer. Those that wish to return to on-site work will also be allowed to do so, as long as local government regulations allow for it.

Image credit HJBC, SeventyFour