DUBLIN-BASED maritime mobile phone operator Blue Ocean Wireless has sold an 11.5 per cent stake in the company for $10 million to NTT DoCoMo, Japan's biggest mobile phone group.

This values Blue Ocean at $87 million just 18 months after it was launched.

The deal was arranged by Claret Capital, the Irish private equity group led by Dómhnal Slattery. Claret is Blue Ocean's biggest shareholder.

Based in Tokyo, NTT employs 22,000 staff and has 53.7 million subscribers in Japan.

The company has a large range of investments in telecom-related businesses across the world, and is listed in Japan, London and New York. It also developed the i-mode mobile internet service.

"This is a great endorsement for the company," Mr Slattery said. "Having NTT on board will bring some gravitas and a new view to the board. It will also give us an opportunity to learn more about trends in the mobile phone market."

Mr Slattery said that the money would be invested in the company's infrastructure.

"The funds will be used to provide the capital for fitting out the ships and supporting the general infrastructure of the business."

NTT was already an indirect investor in the Irish company through its stake in Philippine Long Distance Telephone Co (PLDT). PLDT is the parent company of Smart Communications, which last year paid $16 million for a 30 per cent stake in Blue Ocean.

It is understood that the Irish company is close to securing additional debt facilities from a financial institution.

Blue Ocean provides mobile phone Sim cards to merchant seamen to enable them to use their phones to contact family and friends while at sea on cargo ships and oil tankers.

It is the first company to provide this service, and has used software developed by Tralee-based company Altobridge.

Previously, crew members were required to use the ship's onboard phone, which was both expensive and lacking in privacy.

Robert Johnson, Blue Ocean Wireless's chief executive, said the company has so far signed up 100 ships for its mobile phone service.

He said the average revenue per unit was currently about $38 a month, and around two-thirds of revenue was driven by texting. "It's steadily rising," he said.

Mr Johnson said the company would reach break even when it had signed up about 1,000 ships, which it hoped to achieve by the end of 2009.

It projecting revenues for this year of $3 million, which it expects to rise to $6 million in 2009.

NTT's investment has diluted Blue Ocean's other shareholders. Claret now holds 34.8 per cent of the business, while Smart is the next biggest investor with 28.3 per cent of the equity. Bank of Scotland (Ireland) owns 8.3 per cent, with Altobridge holding just more than 17 per cent of the shares.

NTT has appointed Mitsuo Yamamoto, executive director of its global business department, to the board of Blue Ocean Wireless.