Bermuda-based Seadrill has announced that North Atlantic Drilling Ltd has acquired its harsh-environment drilling activities for $4.1 billion.The acquisition, which was successfully completed last month, follows North Atlantic Drilling’s private placement of 250 million new shares in February and the securing of a $2 billion loan facility.North Atlantic assumed approximately $2 billion in existing debt and payment obligations which will be refinanced by drawing down the loan facility this month.As a consequence of the closing, the right for North Atlantic Drilling’s shareholders to put their shares to Seadrill at the original issue price of $1.70 per share will expire at close of business Oslo time on April 14, 2011.All 1,050 employees involved in the operations of the five existing operating units have accepted to be transferred from Seadrill to North Atlantic Drilling.