Saying their early investor was the CIA isn’t exactly controversial. It’s cited in almost every article about the company. When something is that widely known, it’s usually not cited.
Title: CIA-backed Palantir adds $50M to its war chest
“Palantir's backers include the CIA's In-Q-Tel venture fund and Thiel's Founders Fund. Its customers include government intelligence agencies such as the National Security Agency.”
Google In-Q-Tel and Palantir and you’ll find 100 other articles about it.
But since you asked, here is an old article about it: https://www.bizjournals.com/sanjose/news/2014/09/15/cia-back...
Title: CIA-backed Palantir adds $50M to its war chest
“Palantir's backers include the CIA's In-Q-Tel venture fund and Thiel's Founders Fund. Its customers include government intelligence agencies such as the National Security Agency.”
Google In-Q-Tel and Palantir and you’ll find 100 other articles about it.