Well it’s a black power propaganda poster and if original it would have been printed by the Black Panthers themselves, not unlikely at their own printing workshop. But they were probably not worried about copyright and there will be a gazillion reprints and imitations around, some actual legit posters, some printed to be sold in head-shops etc. I’d say to look for does the paper feel 40+ years old? Does it look like screen printing or possibly stencil or offset? Any digital method is a dead giveaway of course. And is there any provenance? No bullshit like “I found it at a thrift store” but actual, verifiable facts. Personally I would only buy this kind of thing from a respected art dealer, and even then chances are probably 50/50 it’s fake.
