A foundational investor in Connecticut tanker owner Diamond S Shipping has continued selling down its stake in the New York Stock Exchange-listed company.

US energy investor First Reserve, Diamond's first backer, has reduced its stake to 2.86m shares and 7.1% of the company, according to a securities filing Monday.

This is down from the 3.55m shares and 8.8% it held at last reporting in December, when both First Reserve and WL Ross Co both took advantage of a sale led by Pareto Securities to pare their positions.