In 1980 Cornelius C. Vermeule put together a list of Roman imperial statues that could be linked to the sebasteion in Bubon, Turkey. Subsequent to this in 1993 J. Inan published a list of some of the present locations, and this was discussed by C. Chippindale and D. Gill in 2000.
Chasing Aphrodite has now reported that the bronze headless statue of Marcus Aurelius in the Cleveland Museum of Art (inv. 1986.5) is on the list of objects that Turkey has requested for return. (The association with Bubon is clearly stated on the Cleveland website.)
Cleveland is apparently unwilling to discuss the matter ("The Cleveland Museum of Art declined to answer questions about Turkey’s claim"). Yet the AAMD guidelines state quite clearly, "AAMD is committed to the exercise of due diligence in the acquisition process, in particular in the research of proposed acquisitions, transparency in the policy applicable toacquisitions generally, and full and prompt disclosure following acquisition" [emphasis mine].
The year of acquisition, 1986, coincides with 5 pieces that Cleveland has now returned to Italy. 1986 is a date when due diligence does not appear to have been of paramount importance to the curatorial team in Cleveland. It is important that Cleveland reveals how it acquired the statue in order to show its commitment to the highest ethical standards.