At Facebook, security is a top priority — security for CEO Mark Zuckerberg, that is.

The social-networking giant spent more than $6.5 million last year on bodyguards and other measures to protect Zuckerberg and his growing family, according to a recent regulatory filing.

The cost to protect Zuckerberg topped $7.8 million in 2014, up from $4.2 million the previous year, according to the document. In all, the company has shelled out $19 million on security for the CEO over the past three years.

He is reportedly so concerned about his own security that he has no less than 16 people protecting him at his Californian home.

According to Forbes, Zuckerberg is the sixth richest person in the world and has previously been threatened by the Isalmic State supporters so a need for security is understandable. But his expenditure on personal protection massively dwarfs that of Apple CEO Tim Cook with the iconic company spending just $275,000 on security for its leader.

In addition to bodyguards, Facebook footed the bill for Zuckerberg’s personal travel on private jets to ensure his safety, as well as the installation and maintenance of alarms, cameras and other equipment at his homes.

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