From The Strad magazine:
The instrument has been valued at between $7.5m and $10m
The ‘Kreutzer’ Stradivarius, due to be auctioned by Christie’s in a sealed bidding process on 18 June, has failed to find a buyer. The c1731 instrument – named for Rodolphe Kreutzer, the great French violinist for whom Beethoven composed his Violin Sonata no.9 – formed part of the collection of reclusive heiress Huguette Clark, who died in 2011 at the age of 104 after spending her last 20 years in hospital. Valued at $7.5m (£4.46m), the instrument was discovered in a cupboard in one of her vacant homes. Christie’s and her Estate ‘are now exploring next steps together.’