Shares in product tanker owner Ardmore Shipping shot up 18% on Tuesday in New York on high trading volume amid rumours that it is the target of merger-and-acquisition activity.

With no obvious news surrounding the company, and the trading out of step with tanker peers, there were rumours that a major private equity investor had taken a stake in the owner.

Ardmore closed at $6.19, gaining $0.94 from its previous close of $5.25.

Chief executive Anthony Gurnee declined to comment in an email message to TradeWinds on Tuesday, other than to reference a comment he had made to a query in August 2018.

"Regarding M&A we are the perennial candidate in the rumor mill and I suppose that won’t change," he had said then.

While available public filings did not show new investment activity in Ardmore, M&A talk is bound to focus on Oaktree Capital Management, which is a 67% holder in Danish product tanker giant Torm.

Torm has a fleet of about 80 product tankers. Ardmore has 25 tankers on the water, including 19 MRs and six chemical carriers.

Ardmore usually trades below 500,000 shares per day. On Tuesday, it traded 2.3m units. Its market capitalisation is about $205m.

Torm shares were up about 2.5% on light trading volume. It has a market capitalisation of around $615m.