Largest theft of books by an individual

The largest theft of books by an individual, as measured by the combined value of the books stolen, was carried out between 1967 and 1978 by Danish academic Frede Møller-Kristensen. He stole books from the Royal Danish Library, where he was Head Librarian in the Oriental Department. Møller-Kristensen was never caught and continued to work at the library until his retirement in 2000. He died of cancer in January 2003. In September 2003 one of the Royal Library's lost books was offered for sale, and investigators were able to trace the item back to Thomas Møller-Kristensen, the librarian's son. A police raid carried out on 5 November 2003 recovered 1,565 books from the homes of Frede Møller-Kristensen's widow, his son and his son's mother-in-law. Another 76 were determined to have been sold between 1998 and 2003. The combined value of these books was estimated at 206 million Krone ($36 million) in a Danish Royal Library report published on 5 January 2005.

As he died without ever having been discovered, the full extent of Møller-Kristensen's crimes remains unclear. He was remembered by his colleagues as a quiet but extremely knowledgeable man. An internal investigation carried out by the Royal Library determined that there are still 600 rare books, stolen from the library between 1967 and 1978, that remain missing. It is not clear if Møller-Kristensen was responsible for these additional thefts (the security at the library was relatively lax during this period) but if he was, that raises the total value stolen to 217 million Krone ($38 million).

The search of Møller-Kristensen's home turned up a substantial collection of bookbinding and restoration equipment, which had been used to remove or conceal the library marks from many of the books he had taken. From this, investigators concluded that Møller-Kristensen stole with the intention of reselling the books, but seems to have been too cautious to offer more than a handful of them for sale during his lifetime. Stolen antique books are famously extremely hard to fence, as the rarity that gives them value also makes them easy to identify.

The Møller-Kristensen family's stash was discovered after his son and daughter-in-law attempted to sell a copy of a 16th cenetury Italian novel called the Propalladia, not realising that only one complete example of this book was known to exist, at the Royal Library. When a rare book specialist at Christies, London, called the Royal Library to check the provenance of the book, the net quickly closed around the Møller-Kristensen family. In May 2004 Eva Møller-Kristensen (the librarian's widow), Thomas Møller-Kristensen (his son) and Silke Albrecht (his daughter-in-law) were sentenced to between two and three years in prison for attempting to sell stolen property.