Mandatory return-to-office policies appear to be pushing workers at major tech companies away from their employers, with measurable effects on how willing people are to stay at companies that require in-person attendance.

A study released this week by researchers at the University of Michigan and University of Chicago found that three large US tech companies - Microsoft, Apple and SpaceX - saw substantially increased attrition, particularly of their more senior personnel, when they implemented strict return-to-work policies in the wake of the COVID-19 pandemic.

While many efforts to study remote work and its effects on the economy have been based on survey data, the authors of this study used publicly available resume data, rather than self-reported preferences, to track the actual effects of back-to-work policies

The three companies were chosen, according to the researchers, because they were among the first to implement return-to-office mandates as the pandemic eased in 2022, and because of their critical importance to the technology sector.

"We estimate nearly identical effects for all three companies despite their markedly different corporate culture and product gamut, suggesting the effects are driven by common underlying dynamics," the report said.

One of the most striking findings, according to David Van Dijcke, one of the study's authors and a Ph.D candidate in economics at the University of Michigan, was that workers in more senior positions were more likely than their juniors to leave a job rather than go back to the office.

"You might expect something different, where younger or more junior employees have matured in or started their first jobs in a remote environment," he said. "But we didn't find anything like that."

The study also found a tight correlation between the rigor of a specific return-to-office policy and its effects on workers, Van Dijcke said. Apple's one day per week policy produced the smallest changes to its workforce, causing about a 4% decrease in senior employees as a share of the overall pool. SpaceX's full-time in-house requirement, by contrast, led to a larger than 15% decrease.

Van Dijcke, who is also employed at the risk analytics division of Ipsos Public Affairs, said that there were several possible reasons more senior tech workers might leave. Another study, he noted, tracked two offices of the same company, located mere blocks apart, and found that employees there got different benefits from working remotely and working in-office.

"They found that senior software engineers were more productive when they were not close to their co-workers, which I guess makes sense, right?" he said. "They're skilled at what they do and benefit from fewer distractions. Whereas if you're more junior you might benefit from distractions that give you valuable feedback."Recent surveys have tracked closely with Van Dijcke and his colleagues' findings, including data published today by Gartner finding that one in three executives would quit over a return-to-office mandate, compared to less than 20% of non-executive workers.

Nevertheless, Gartner said that in-office requirements are getting more strict across the technology sector. Dell, for instance, has begun to issue employees color-coded "grades" based on their attendance.