Oslo, Norway – 11 August 2025 – Dolphin Drilling AS (“Dolphin Drilling” or the “Company”, OSE: DDRIL) provides the following update further to the decision of the UK Supreme Court on 24 June 2025 in which an appeal, by Dolphin Drilling Limited (“DDL”), in respect of a historic corporation tax liability to His Majesty’s Revenue and Customs (“HMRC”), was dismissed.

The Company today reports that DDL has, in the period since 24 June 2025, engaged in discussions with HMRC, and that DDL has today made an initial payment to account in the sum of £2,000,000 in part settlement of the said liability (which, prior to the said payment to account, was in the approximate total sum of £14,200,000).

The Company also today reports that DDL continues to engage in further discussions in respect of the settlement of the remaining balance of the said liability, and confirms that any material developments shall be the subject of separate updates to the market.

For further information, please contact:
Ingolf Gillesdal, CFO, +47 920 45 320

About Dolphin Drilling AS:

Dolphin Drilling AS is an Oslo listed, Aberdeen head-quartered, company which owns and operates a fleet of harsh environment mid-water & deep-water semisubmersible drilling rigs, capable of working worldwide.