The Wall Street Journal reports on an interesting 100-year sharing agreement between the New York Public Library and the Commonwealth of Pennsylvania for a manuscript Bill of Rights.The NYPL received the manuscript on donation in 1896 and its provenance before then appears to be uncertain. The WSJ article notes that only fourteen copies of the Bill were made (one for each state and for the federal government) and that Georgia, Maryland, New York and Pennsylvania are all missing their copies. Georgia's and New York's were probably lost to fire. (NYS's great and tragic 1911 Library fire destroyed a lot of early state history, including a lot of colonial era manuscripts.)
What's suggestive in this case, and merely alluded to, is that North Carolina had used replevin (and a sting operation) in 2003 to get possession of a Bill of Rights that had got into private hands back in the Civil War (when it had been looted by a Union soldier). It's possible that replevin litigation had been raised with the NYPL. (As the linked North Carolina press release above makes clear, Pennsylvania had been approached regarding sale of the NC document. Also, this brief review by Elena S. Danielson in American Archivist, beginning p.11, notes some of the other legal issues, and make clear that the Union soldier should have returned his illegal loot; the same review on p.14 notes the current legal approaches, which vary from state to state, which includes preserving the documents and making them available to the public.)
Not mentioned in the WSJ article is the Bill of Rights at the Library of Congress, whose original owner cannot be identified. Is it the federal copy? Another state's copy? It was donated (per Danielson's review) during WWII through the good offices of the legendary Americana dealer Dr. A.S.W. Rosenbach.
It's not entirely clear that the Bill of Rights at NYPL is the Pennsylvania copy, and the NYPL, even though it restricted access, did preserve the manuscript and make it available to researchers and for limited exhibition. Pennsylvania had been anxious to acquire a copy for its Constitution Center in Philadelphia, so this is a good deal, and is much cheaper than an outright purchase or litigation. (And litigation is no sure thing: the State of Maine lost litigation in attempting to get apparently official printed copies of the Constitution out of private dealer hands. Again, the Danielson review does a nice job of summarizing these points.)