Any company or organization can use what's called a "canary trap" to try to ID leakers. Reporters - you can always just transcribe, describe or quote source materials like emails, memos, etc. if you're not sure if you'd reveal a source by showing a complete image of something leaked to you.
Comments
"After... leaks at Tesla... in 2008, CEO Elon Musk reportedly sent slightly different versions of an e-mail to each employee... The plan was undermined when the company's general counsel forwarded his own unique version..."
https://en.wikipedia.org/wiki/Canary_trap
Is that akin to the "we've never been subpoena'd by the government" statements?
If I tell Susie there will be chocolate cake at the party and Bobby there will be vanilla cake and at the party, Jimmy says “where’s the vanilla cake?” I can legally execute Bobby
https://bsky.app/profile/altnps.bsky.social/post/3lh626ftypk2f
Also be wary of exact quotes - an old technique is to subtly vary controversial statements that are likely to be quoted. Easy with small distribution lists, slightly harder at scale.
https://www.grammarly.com/ai/ai-writing-tools/rewording-tool
INPUT: A man walked into the Treasury Department carrying a briefcase.
OUTPUT: A gentleman entered the Treasury Department with a briefcase in hand.