Experts sceptical about claims made by company that says it has found the Dmitrii Donskoi, which went down during 1904-1905 Russo-Japanese war

A South Korean company’s claim to have found a sunken Russian warship has triggered a frenzy amid speculation the ship was carrying an enormous amount of gold when it sank 113 years ago.

The Seoul-based Shinil Group said its divers discovered a wreck it identified as the 6,200-ton Dmitrii Donskoi, which went down during the 1904-1905 Russo-Japanese war off an eastern Korean island. The company speculated that 200 tons of gold bars and coins ) would probably still be aboard the ship, and claimed that this would be worth 150tn won ($132bn). However, this appears to be a huge overvaluation: the Bank of Korea’s 104 tons of gold reserves are valued at around $4.8 billion.

Shinil released photos and videos taken by search submarines, which showed markings on the stern the company said was the ship’s name in Russian. It said it hoped to hoist the ship from its depth of around 400 metres within months.

Other companies have made similar claims, but none has taken steps toward raising the wreck. One of them, Dong-Ah Construction, was accused of spreading false rumours to bump up its stock prices and later went bankrupt.

Shinil is unlisted but its president recently agreed to acquire shares in a local company, Jeil Steel.

After Shinil’s announcement on the Russian ship, Jeil’s stock prices rose by 30% on South Korea’s Kosdaq market. They continued their steep rise on Wednesday morning before Jeil in a regulatory filing clarified that Shinil’s president would be its second-largest shareholder, not the largest, if the deal goes through. Jeil also said it has “no relation to the treasure ship business”. Jeil’s stock prices dropped more than 20% after Thursday’s trading.

South Korea’s financial supervisory service said it is closely monitoring trade activity involving the shares of Jeil Steel. An agency official said it was watching for possible deceptive practices involving the trade of Jeil shares, including inducing investors through false information.

“Investors should beware because it’s uncertain whether the ship is salvageable and whether Shinil would be able to gain ownership of the assets even if it gets permission to raise it,” said the official, who did not want to be identified, citing office rules. “Dong-Ah Construction made similar claims over the same ship but failed to deliver on its promises and went bankrupt, causing huge losses for investors.”

Russian scholars have said in the past that Russia was unlikely to put so much gold on a single ship and it must have been much safer to move it by train. They also have said some gold coins could have been aboard the ship to pay the salaries of Russian navy officers.

It is unclear whether Shinil would receive South Korean government approval of its salvage plans.

Local laws aimed at preserving national territory and property require the company to deposit 10% of the estimated value of the shipwreck before starting its salvage works.

Shinil disagreed on the amount of its possible deposit, saying what it has officially located was the shipwreck, not treasures on it. It estimated the shipwreck’s value at 1.2bn won ($1 million) and planned to put down 120m won ($105,540) as a deposit. Company spokesman Park Seong-jin said his company will file a request for the ship’s salvage right.

Some experts also said it is unlikely the Donskoi, a thickly armoured warship with more than 12 artillery pieces, 500 sailors and presumably 1,600 tons of coal, would have had room for 200 tons of gold, which would be double the current gold reserves at South Korea’s central bank.

Even if the ship is hoisted and treasures are found, their ownership could be disputed.

A South Korean financial ministry official responsible for the issue said Russia may be able to claim ownership. Park disputed that, saying 80% of the potential treasures would belong to the company while the rest would go to a South Korean government coffer. He cited related South Korean law and an international court ruling on a similar case.