Public museums in the Netherlands were set to relinquish more than 200 Old Masters after the Dutch government agreed last week that these artworks had been looted from Jacques Goudstikker, a prominent Jewish art dealer in Amsterdam, and thus do not belong to the state. Goudstikker died in 1940 while fleeing the Nazis. His heir is Marei von Saher, the widow of Goudstikker's son. Von Saher, who lives in Connecticut, had been unaware of her father-in-law's losses until 1997, when she was contacted by Pieter den Hollander, a Dutch journalist researching post-war restitution in the Netherlands. She is seeking another 1,000 artworks that had been in the Goudstikker collection, and has filed claims in museums around the globe. She recovered an Edgar Degas drawing, Four Nude Female Dancers Resting, from the Israel Museum last March. In another significant art case, Austria in January agreed to return five paintings by Gustav Klimt to the heirs of Ferdinand Bloch-Bauer. The Czech-Austrian sugar magnate fled from Vienna in 1938, and his assets were expropriated. He died in exile in Switzerland in 1945. The estate he bequeathed to his nieces and nephew included the five paintings. The Klimts, which are valued at as much as $300 million, include an iconic portrait of Ferdinand's wife, Adele, which has been referred to as the "Austrian Mona Lisa." Bloch-Bauer's surviving niece, Maria Altmann, claimed the Klimts seven years ago, using documents unearthed by Austrian journalist Hubertus Czernin in his country's federal archives to support the Bloch-Bauer heirs' title to the artworks. In yet another high-stakes restitution case, a German court last December affirmed the claim to prized properties in the heart of Berlin by the heirs of the Wertheim family, former owners of the prominent German department store chain. The family was dispossessed during the Nazi years and later defrauded of its stake in the retail giant. The real estate of the business properties is valued at some $350 million. The heirs' claim was based on materials discovered by Simone Ladwig-Winters, a graduate student in Berlin digging in archives as she researched her thesis on the Wertheim company. THESE CASES demonstrate that, two generations after the Holocaust, the ability of Nazi victims' descendants to identify their losses and to assert successful property claims often depends on serendipitous and timely discoveries of materials by independent sources. Researchers and reporters found the evidence that establishes Jewish ownership history, documents property losses and verifies that those losses were due to Nazi persecution. It is a strange phenomenon that staggering claims would originate with the random investigations of scholars and journalists. What would have been the fate of the Goudstikker artworks if, say, den Hollander had chosen to focus instead on the lost art collection of businessman Franz Koenigs? Or if Czernin had been less thorough in the Austrian archives? More important, though, is another aspect of what these academic and journalistic investigations reveal: that the heirs of Nazi victims may be woefully ignorant of their family legacies. Barbara Principe, for instance, was six years old when her family fled Berlin after Kristallnacht. She grew up on a chicken farm in southern New Jersey unaware of the fortunes of her Wertheim family. Unlike dormant accounts in Swiss banks and Nazi-era insurance policies purchased in Europe, for which massive research has been undertaken and paid for by commercial enterprises, artworks and real estate are properties that must be sought out and fought for, one by one. The overwhelming majority of losses are not Old Masters or coveted parcels of land near Potsdamer Platz. They are artworks, ceremonial objects and houses of much less financial worth, but of no less emotional value. Restoring these properties to their rightful owners requires concerted and sustained intervention, not the limited and haphazard interests of scholars and journalists. More than seven years ago, 44 nations sent delegations to the US State Department for a conference on Holocaust-era assets. They pledged to help identify Nazi loot. Many have taken some steps. American and German museums, for instance, publish on the Internet objects in their collections that have gaps in provenance for the years 1933-1945. However, it is rare for a museum to make the effort to fill the gaps or find the original owners' families, who likely are now scattered around the world. The onus remains on survivors and heirs to come forward with documented claims. Unless governments, museums and Jewish organizations are willing to commit the funds to conduct the extensive research necessary to finally and fully document what was confiscated and from whom, Nazi victims, their heirs and the Jewish world collectively run the real risk of losing their legacies forever. The writer is author of a book on the Conference on Jewish Material Claims Against Germany, to be published later this year by Vallentine Mitchell (London).