Will Finders Be Keepers of Salvaged Treasure?

The Odyssey Explorer remains docked here, at a cost of more than $20,000 a day, company officials said. "We have nothing to hide," said Aladar Nesser, a former U.S. Navy officer who is now Odyssey's director for international business development. "But we're afraid they'll confiscate everything on it."

Archaeologists, historians and treasure buffs also joined in the hunt for the Black Swan, which took them to the Federal Admiralty Court in Tampa, where filings by Odyssey hint that the firm has found three of the most significant shipwrecks ever.

The papers, in which Odyssey asks to be named "custodian" of the wrecks, do not name any of the ships and give only vague descriptions of their graves, but undersea archaeologists and other experts say there is little doubt what they refer to: the Nuestra Señora de las Mercedes; the Merchant Royal, a 36-gun British navy vessel that sank in 1641 in bad weather off southwestern England with a fortune in silver, gold and jewels; and the SS Ancona, an Italian passenger liner torpedoed by a German U-boat in 1915 off the southeastern coast of Sardinia, taking 12 barrels of gold and a shipment of silver bars with it to the bottom.

Spain has filed to compel Odyssey to disclose the three sites, contending that some of the ships might have been Spanish naval vessels; if they were, they would be covered by sovereign immunity and would still belong to Spain even if lost in international waters. In another legal scenario, the treasures they carried might have belonged to the Spanish government, which could now file claims for them.

Either way, the judge in the case could still award Odyssey a reward for salvaging the vessels, ranging from a pittance to the entire wreck, Texas A&M's Delgado said.

If the court rules that one of the wrecks is the Nuestra Señora de las Mercedes, legal experts say, Spain will certainly claim that it has sovereign immunity and that it lost but never abandoned the ship, a key criterion.

Much of what was recovered was in the form of large, rocklike collections of encrusted coins, weighing an average of 60 pounds apiece and discovered in a "debris field" rather than in a single area that might be the remains of a ship, according to Odyssey's Nesser. That suggests that people aboard the ship might have thrown the cargo overboard to try to prevent a sinking, he said.

Underwater and treasure Web sites, which are brimming with online chats about the Black Swan, have suggested that the absence of a ship indicates that the booty was from the Spanish galleon, which by some accounts disintegrated in a tremendous explosion.

Citing comments by Stemm, some online participants have speculated that the company is preparing to argue that the loot was, in fact, abandoned by people throwing it overboard.

Odyssey remains mum on the location. "We are very, very concerned about protecting that site, and it is irresponsible for people to try to figure out where it is," Stemm said. He compared giving hints about it to dropping clues about the location of someone in a witness protection program.

"It's in the Atlantic," he said. "I'm not going to get into guessing games."