Well, the initial owner buys (or receives as a gift) the painting directly from Picasso. That's an easy one!
It gets more complicated later: experts assess the credibility of the painting by examining the ownership history, if available, the signature on the painting, the quality of the work, chemical properties of the pigments and canvas, etc. They sometimes get it wrong, though (cf. Beltracchi!). It's more a probability that a work is genuine, rather than a 100% certainty.
It gets more complicated later: experts assess the credibility of the painting by examining the ownership history, if available, the signature on the painting, the quality of the work, chemical properties of the pigments and canvas, etc. They sometimes get it wrong, though (cf. Beltracchi!). It's more a probability that a work is genuine, rather than a 100% certainty.