It was offered in the Entertainment & Memorabilia auction held by Ewbank’s (24% buyer’s premium) of Send.
Another example of this ‘well thumbed’ approach was seen in the most recent online On the Shoulders of Giants sale held by Christie’s (25/20/13.5% buyer’s premium).
That May 16-23 auction contained some much more expensive items by Hawking, Richard Feynman and others to which I will return at a later date, but £4200 secured a first US edition of the book in which the thumbprint was verified by Judy Fella.
Hawking’s first secretary and later PA and nursing co-ordinator, Fella had worked with him on the first draft.
Both results, however, are dwarfed by the sum paid for a copy in the 2018 sale branded On the Shoulders of Giants, held by Christie’s. Another first US edition, bearing the famous thumbprint but no other annotation, had been estimated at £2000-3000 but sold for £55,000! This was one of the lots from the Stephen Hawking family estate.