Ashurst advised Tullow Oil plc and its Ugandan subsidiary, Tullow Uganda Limited, in successfully defending appeal proceedings in the Court of Appeal. The appeal by Heritage Oil and Gas Ltd and Heritage Oil Plc ('Heritage') sought to overturn the decision of the High Court regarding Tullow's indemnity claims against Heritage Oil concerning a capital gains tax payment that Tullow had made on Heritage's behalf to the Uganda Revenue Authority.

In August 2013, Tullow received $345.8 million from Heritage in satisfaction of this High Court judgment.  In September 2013, Heritage was granted permission by the Court of Appeal to appeal certain aspects of the High Court judgment and the appeal was heard in May 2014. In its judgment, the Court of Appeal ruled in Tullow's favour on all but one of the points appealed by Heritage. This point relates to part of one of Tullow's indemnity claims and will require Tullow to repay to Heritage approximately $2.5 million plus some interest. In all other respects the Court of Appeal has upheld the High Court's judgment.

The Ashurst team was led by dispute resolution partner Ronnie King and senior associate Tom Cummins, together with David Wolfson QC and Richard Mott of One Essex Court.

Commenting, Ronnie King said:

"We are delighted to have worked with Tullow on this significant matter. The dispute involved highly complex issues, including issues relating to Ugandan tax law and English law contractual interpretation.  We are very pleased to have assisted our clients in obtaining such favourable judgments in both the High Court and before the Court of Appeal".