Atlanta recently bought collection of MLK papers from Southeby's -- who actually owned these and how?

Question

Just curious as to who actually owned the MLKing papers recently purchased by Atlanta for $32 m from Sotheby's. Did the auction house itself own them, or were they acting on behalf of another owner? How did this collection get put together. One would think the King estate or Mrs. King (until last year) would have controlled these documents.

Answer 1

The King family(estate) put them up for sale and got the money.