() – Ensco Rowan’s investor Luminus Management on Wednesday urged the deep-sea oil driller to sell guaranteed bonds to fund a special dividend of $2.5 billion, sending the company’s shares down nearly 7% to their lowest in more than two decades. The investor in a letter to the company’s board said it was disappointed by the stock’s performance despite the acquisition of smaller rival Rowan Cos Plc for $2.38 billion in April. A commitment to pay out the dividend should lead to an immediate re-rating of the stock, according to Luminus, which said it owns a 4.5% stake in the London-based company. Ensco Rowan’s shares have lost more than half their value since the merger closed on April 11. They were down at $7.07 in morning trade, giving the company a market capitalization of about $1.40 billion. The offshore driller was worth $332.96 per share at its peak in 2008. Reporting by Arundhati Sarkar in Bengaluru; Editing by Shailesh Kuber and Sriraj KalluivlaOur Standards:The Thomson Trust Principles.