[williamsmj]

Correct. Like many credulously repeated stories about Musk 1) the source for this one is Musk himself 2) the description that he gave, and that gets repeated in viral posts, is an extremely easily disproven lie.

https://en.wikipedia.org/wiki/Canary_trap#In_popular_culture

"After a series of leaks at Tesla Motors in 2008, CEO Elon Musk reportedly sent slightly different versions of an e-mail to each employee in an attempt to reveal potential leakers. The e-mail was disguised as a request to employees to sign a new non-disclosure agreement. The plan was undermined when the company's general counsel forwarded his own unique version of the e-mail with the attached agreement. As a result, Musk's scheme was realized by employees who now had a safe copy to leak."