In 1983 the USA ratified the 1970 Unesco Convention on the Means of Prohibiting and Preventing the Illicit Import, Export and Transfer of Ownership of Cultural Property (Paris, 14 November 1970). Article 7 includes the statement,

To take the necessary measures, consistent with national legislation, to prevent museums and similar institutions within their territories from acquiring cultural property originating in another State Party which has been illegally exported after entry into force of this Convention, in the States concerned.

In 2002 the Princeton University Art Museum agreed to return the fragmentary pediment of a Roman funerary relief that it had acquired in 1985 from New York dealer Peter Sharrer with funds provided by Mr. and Mrs. Leon Levy (inv. 85-34: Princeton University Art Museum 1986, 38, 39 [ill.]; Padgett 2001b, 47-51, no. 11). It turned out that the fragment had been discovered in 1981-82 at Colle Tasso near Tivoli and had been published by Zaccaria Mari. Michael Padgett, the then curator at Princeton and who was preparing a catalogue of the Roman sculptures, notified the museum’s acting director who in turn contacted the Italian authorities (Anon. 2002). Susan M. Taylor, the museum’s newly appointed director, was quoted in the press release about the return: “We are proud to be an active partner in the ongoing international effort to resolve ownership claims for stolen objects and in discouraging the illegal trade of art and cultural artifacts.” 

This was not to be the end of the museum’s return of antiquities.