During the 1970s the Royal Library suffered numerous book thefts, primarily from its old collections.The case was handed over to the police who conducted extensive investigations and searches for stolen books via Interpol and the international antiquarian book trade. In spite of these efforts, the crime was not solved. The library established several new security measures in the course of the 1970s, as a result of which the thefts stopped.
In the period between 1979 and 1999 the library conducted a total inventory of its old collections in order to determine the extent of the thefts.
In 2003 the library was contacted by the British auction house Christie's about some books that Christie's had received for sale. These books turned out to have been stolen from the Royal Library during the 1970s. The police were notified, and several persons were subsequently convicted.
Read more about the case here:
Lists of books retrieved: