Rich-lister Sir Own Glenn is claiming victory after the High Court in England and Wales ruled his former business partner Eric Watson had engaged in "deliberate deception" when the pair set up a joint venture.

Glenn had seen a large chunk of his fortune tied up in the arrangement, and had spent the past five years fighting in the English and British Virgin Island courts to extricate himself and his £129m ($250m).

In an accompanying press release, Glenn said: "I regard this judgment as a complete vindication of my position."

"Eric Watson has behaved appallingly. I saw him as a close friend but he was trying to defraud me. Once I knew what had happened I was determined to get justice."

The long-running dispute may have a wee way to run yet, with Watson saying through a spokesperson he was "disappointed" with the judgment and was intending to appeal.

"This is by no means over," he said in a statement.