Facebook parent Meta PlatformsCNBC has been informed that Covid boosters will not be required for employees to enter its U.S. facilities. A spokesperson said Friday to CNBC.

Many technology companies are now trying to lure their employees back to corporate campuses. Meta as well MicrosoftOn Monday, a wide range of U.S. offices reopened.

The spokesperson said that they had updated their requirements to conform with CDC guidelines in March. Covid-19 boosters no longer are required for entry. However, it is strongly advised.” The primary vaccine requirement, which is one or two shots per series of vaccinations, remains unchanged.

This change comes just three months after social media operator announced rulesYou can return to work.

Meta spokeswoman did not give any explanation.

Meta’s headquarters is in California. According to New York Times data 71% have been fully vaccinated and 35% have had a booster shot. The newspaper data indicates that the number of cases has fallen in January.

AppleAlso based in California, the company requires all employees to prove they received a booster shot. the VergeReports from January

Tuesday was the U.S. Food and Drug Administration authorizedA second Pfizer-BioNTech or ModernaA booster shot is required for anyone 50 years or older within four months of receiving the initial booster.

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