According to foreign technology media MarketWatch reports, Apple recently submitted to the U.S. state of California documents show that has fired 618 security and related personnel located in Silicon Valley and other office locations in the state.

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An Apple spokesperson later told the media that the firing was mainly due to a change of security company, and that the new security company had rehired most of the security personnel, except that the spokesperson did not reveal the specific numbers.
The Apple spokesperson as follows:
We have added several new security companies to jointly provide security services for our campus. Most of the security personnel affected by this transition have already accepted positions with the new vendors, and we are working closely with our partners to ensure a seamless transition.
Apple is the only technology company with a market cap of more than $1 trillion that has not announced layoffs to date, MarketWatch noted. A company spokesperson declined to say whether the change in security provider was a cost-cutting move, but said the move would not significantly reduce the number of security guards at Apple buildings.