Billionaire Alex Gerko is shutting down the investment partnership at the center of a recent UK Supreme Court case, drawing to a close the long-running dispute over levies on historical trading profits. HFFX, a fund Gerko ran while at London-based money manager GSA Capital Partners between 2010 and 2015, is taking steps to close voluntarily, according to registry filings, two months after the UK entity and the tycoon lost a legal case over taxes on deferred payment plans.

The fund ceased its investment operations in 2015, when Gerko founded his quantitative trading firm, XTX Markets, after leaving GSA that year.