Today Makes Tomorrow (TMT) chairman Nobu Su is engaged in a legal fight with the Connecticut investment banking arm of Royal Bank of Scotland (RBS) over allegations it is withholding the shipping tycoon’s shares in Star Bulk Carriers.

In the lawsuit, which was filed in October but has only now come to light, Su holding company F5 Capital alleges that RBS Securities has wrongfully failed to turn over nearly 414,000 Nasdaq-listed Star Bulk shares, despite repeated requests.