ExxonMobil is closing down tanker vetting division IMT and handing all ship vetting over to Maritime Global Services, a new Glasgow-based arm of the Stena group's Northern Marine Management.

Singapore-based IMT is the former in-house tanker owning entity International Marine Transportation, which became an in-house tanker vetting operation when ExxonMobil got out of shipowning.

The move is long-planned. The Maritime Global Services website gives its headquarters address as the Glasgow offices of Northern Marine. It identifies no personnel, but TradeWinds understands the company has 15 staff in Mumbai, its main operational centre, plus a few others in Glasgow, Singapore and Houston.

The head of the Mumbai office will be a Northern Marine staffer and the number two will come from IMT.

Northern Marine officials did not immediately respond to an enquiry from TradeWinds.

TradeWinds understands the 45 employees of Singapore-based IMT are retiring, being reassigned, or taking buyouts. A few will go to the new operation or stay on with IMT to complete project assignments for third parties, but otherwise IMT will be closed down as of 1 July.

A source with insight into the move told TradeWinds an attrition of technical know-how is behind the end of IMT.

"The companies have been in discussions for over three years," said the source, who spoke to TradeWinds on condition of anonymity. "It was initiated by the ExxonMobil side. After 15 years of operating without ships of their own, they found they had exhausted their internal supply of maritime competency."

The source added that ExxonMobil considered giving the job to other companies including Petronas. Northern Marine won out and set up Maritime Global Services for the purpose, in part thanks to ExxonMobil's history with Northern Marine. The Stena subsidiary formerly supplied crew for IMT tankers.

IMT moved its headquarters to Singapore in 2014 but still has personnel at its old UK offices at Leatherhead.

According to the Singapore website of ExxonMobil, IMT screens some 55,000 vessels and prepares 700 ship inspection reports and 120 marine security reviews a year.

IMT was in operation for over a century, beginning in the US as an arm of Socony-Vacuum, one of the corporate ancestors of ExxonMobil.

The company's most famous ship was the 211,469-dwt Exxon Valdez (built 1986), which the UK-based incarnation of IMT owned for a time after ExxonMobil transferred the ship out of the US flag.