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MADRID - An international court battle looms over disputed ownership of the world's richest sunken treasure trove, as Spain prepares to sue the US exploration company Odyssey Marine Exploration for withholding crucial information about its latest find.
The Spanish action is a riposte to the Florida-based company's efforts to protect the secrecy of a shipwreck it has found: Odyssey demands compensation from Spain for "appalling interference" in its operations, allegations that Madrid dismisses as "baseless".
The stand-off is the tensest yet in the clash of cutlasses over whether the US treasure hunters are secretly plundering a wrecked Spanish galleon - or possibly a British vessel containing captured Spanish booty.
Behind the transatlantic flurry of writs lies a buccaneering operation as ruthlessly cutthroat as the imperial rivalry that sent chests of gold and silver plunging to the ocean floor in centuries past.
Two of Odyssey Marine's survey vessels have been moored off Gibraltar for months, using the British colony as a base for explorations in waters south and west of Spain.
The western Mediterranean is a graveyard of hundreds of sunken Spanish, French and English ships, scuttled by storms or pirates during Spain's long marine supremacy.
For four centuries fleets of Spanish galleons spanned the globe carrying gold and silver plundered from Spain's American colonies.
The latest legal tussle followed the departure from Gibraltar last month of Odyssey's survey ship Ocean Alert.
Spanish police stopped and searched the vessel, forcing it into port at Algeciras, where they confiscated a computer belonging to the company's lawyer.
Odyssey complained Spain had no business hijacking Ocean Alert in international waters, but police insisted they were acting in accordance with a court order, and that the waters were Spanish.
Odyssey's other ship, Odyssey Explorer, remains moored in Gibraltar, and faces a Spanish blockade if it tries to leave.
Odyssey announced in May it had found a wreck codenamed "Black Swan" containing 500,000 pieces of gold and silver dating from Spain's colonial period worth at least $500m ($676m), the biggest such haul to date.
The company would not reveal the site of this fabulous discovery, but insisted it was in international waters "somewhere in the Atlantic".
Seventeen tons of coins were hauled from the seabed, packed into 2,800 containers and shipped to Gibraltar in the holds of Odyssey's two explorer ships, then whisked to the company's Florida's offices "for cataloguing" in a cargo flight from Gibraltar.
The operation, conducted under the nose of outraged Spanish authorities, prompted Madrid to sue the company for "suspected plunder".
Madrid has been trying ever since to establish what was taken, and from where.
"Spanish and international laws protect us and if anything against the law has occurred we will respond, and what was ours will be returned to Spain," the Culture Minister, Carmen Calvo, said.
Spain believes the wreck could be one of many Spanish galleons that sank around its coasts - the Santa Cruz (1554), the Nuestra Senora de Aranzazu (1614) or the San Cristobal (1757) - their holds groaning with treasure.
But even if the ship were not flying the Spanish flag and it sank outside Spanish waters, if the bullion were Spanish ingots, doubloons or pieces of eight captured by an enemy ship, then Spain still claims the trove, wherever it went down and whatever ship was carrying it.
"Spaniards can be assured that we will not permit this shameful plunder to take place," Ms Calvo said.
Odyssey refuses to give the exact location of its latest find, and says it is not sure of the ship's identity.
"We don't yet know which country has the right to the Black Swan.
Various countries could lay claim to colonial wrecks, and we are engaged in a process of research," the company says.
Their secrecy fuels feverish speculation that the wreck may not be Spanish at all, but British.
It could be the remains of the Merchant Royal, which went down 40 miles south-west of Land's End near the Scilly Isles in 1641, laden with treasure brought from Mexico that originally belonged to Spain, and on which Spain might have a claim.
Or it could be the warship HMS Sussex that sank in a storm off Gibraltar in 1694 carrying 10 tons of gold and 100 tons of silver.
That treasure was a secret payment from England to the Duke of Savoy, intended to buy his allegiance in a campaign against France.
The Royal Navy originally gave Odyssey Marine permission to scour the seabed, and to dock in Gibraltar - to Spain's intense displeasure - in the expectation of discovering British treasure.
Any trove would be split 50-50 between Britain and the US company.
Spain seems reluctant to contemplate a similar shareout.
The treasure hunters insist they are a serious scientific operation carrying out exploration that others have neither the resources nor the deep-sea technology to pursue.
They justify their secrecy by saying that identifying the site of the treasure would offer an invitation for unscrupulous modern-day pirates.
Spain, by contrast, accuses Odyssey Marine - a commercial business whose shares are listed on Nasdaq - of privateering their historical heritage that should remain in Spanish hands.
However, this patriotic zeal is comparatively recent: for years, Madrid showed little interest in its marine heritage, Spanish archaeologists say.
- INDEPENDENT
