The piece is an inkjet print on a plexiglas triptych and is part of an edition of five.
Marshall, of course, is one of the world's most prominent contemporary artists. Last May his painting, Past Times, sold for ove $21 million dollars (and purchased by Sean Combs). The study for Past Times (a work on paper) just sold at auction for 1.8 million dollars. The study was put up for sale by Chicago-based art consultant Joel Strauss. Strauss intends to pay a royalty to Marshall (how much would be interesting).
He was born in Alabama, grew up in Los Angeles and now lives in Los Angeles. The recipient of a MacArthur "genius grant," Marshall's work and influence, his rise, is impossible to go into in such a small space. You can read more HERE and HERE....and a bunch of other places.
You should read about him as you can make a strong argument that he is the most important living American artist and this isn't about the price of his paintings alone.