US firm Covington & Burling has bagged a lead role advising the Spanish Government on a claim arising from the discovery last month of a shipwreck carrying treasure thought to be worth $500m (£252m) – thought to be the largest discovery of its kind.

The claim, filed against US marine explorers Odyssey Marine Exploration in the US Federal Admiralty Court last week (30 May), challenges the explorers' rights to recover or possess any Spanish property from the sunken ship, which dates from the 17th century.

Washington DC-based Covington litigation partner James Goold is acting for the Spanish Government.

Allen von Spiegelfeld of Florida firm Fowler White Boggs Banker is advising Tampa-based Odyssey.

The ship is thought to contain more than 17 tons of silver and gold, some of which has been recovered from the wreck and sent to the US for examination.

Goold commented: "Salvage operations without Spanish permission are not acceptable. Odyssey has failed to respond to numerous requests for disclosure of information concerning the identity of the ship and the material recovered."

He added: "We will establish that Spain remains the owner of this sunken cultural heritage and may protect that heritage by legal action for its recovery and return to the country of origin."

Goold has successfully acted for the Spanish Government in shipwreck cases before, most notably on the recovery of material from two ships, Juno and La Galga, in 2000.