Fantastic Forum the Original Art Bell's Midnight in the Desert and Coast to Coast AM Forum

They’re almost invisible but contain a hidden code – and now their presence on a leaked document has sparked speculation about their usefulness to FBI investigators. FULL STORY

I think I first about this on an NCIS episode a few years back.....

I wonder if there is any way of removing them?? (It probably tells them where it was printed,etc)

I have heard of em......