Want to delete that embarrassing message you just sent? WhatsApp will let you, and so will Instagram — but if you’re using Facebook, then you’re out of luck.

Unless you’re Mark Zuckerberg, the CEO and cofounder of Facebook.

TechCrunch reported Thursday that some old messages sent by Zuckerberg and senior executives have disappeared from recipients’ Facebook Messenger inboxes, proven by the original email receipts sent at the time.

The company appeared to confirm the unique arrangement, telling TechCrunch the change was made in response to an uptick in hacking.

“After Sony Pictures’ emails were hacked in 2014 we made a number of changes to protect our executives’ communications. These included limiting the retention period for Mark’s messages in Messenger. We did so in full compliance with our legal obligations to preserve messages,” the company said.

The Sony hack targeted the emails of Sony film executives, which revealed a side of Hollywood rarely seen by outsiders, and the decision to name the event as a catalyst for Facebook’s message purge indicates how troubling the incident was in Silicon Valley — and that Facebook was concerned about being hacked.

The company also raised the idea of a “retention period,” though there is no such thing for normal users. If a user long presses a private message on Facebook a “Delete Message” pop up confirms that the function will “delete your copy of the message,” and the recipients’ copy will remain.

Facebook-owned Instagram has long had the option to “unsend” direct messages, while Facebook-owned WhatsApp recently launched a deletion function where unread messages can be deleted “for everyone.” A message is then displayed to all participants that content has been deleted.

But Zuckerberg’s deleted messages didn’t leave behind any such message, probably because they had already been read, many years ago.

The messages were originally sent to former employees and people outside of Facebook. According to TechCrunch, the recipients of the now-deleted messages were not informed at any stage that correspondence they received had been erased.

Zuckerberg may be the CEO of Facebook, but it’s unclear how the decision to remove senior executives’ messages would be allowed under the company’s terms of service. The terms only allow Facebook to remove content if the company believes “that it violates this Statement or our policies” or for infringing copyright.

Deleting messages quietly, and selectively, also appears to fly in the face of Facebook’s campaign to “make the world more open and transparent.” Its own policies say that the company “should publicly make available information about its purpose, plans, policies, and operations.”

Facebook appears to have not followed these policies in this instance, and it raises questions about the recipient’s right to privacy.

The news comes just weeks after the Cambridge Analytica scandal which has seen Zuckerberg admit that tens of millions of users probably had their data scraped.