The shares of Bermuda-based run-off specialist Enstar Group Ltd soared more than six percent in New York Stock Exchange trading on Friday after the company announced that second-quarter earnings more than quadrupled.Net earnings were $40.7 million, or $3.02 per share, Enstar announced after the markets closed on Thursday, compared to $9.4 million, or 66 cents per share in the same period in 2011.In Friday trading, the shares climbed $5.55, or 6.1 percent, to end the week on $97.03.Enstar, which acquires and manages insurance and reinsurance companies and portfolios in run-off, has seen strong growth in recent years, boosted by the sale of a 20 percent stake in 2011 to GS Capital Partners, a private-equity fund controlled by Goldman Sachs.Shareholders’ equity at June 30, 2012 amounted to $1.44 billion, excluding non-controlling interest of $249.3 million, which was up from $1.39 billion, excluding non-controlling interest of $297.3 million at the end of last year.In the balance sheet detailed in its 10-Q filing to the US Securities and Exchange Commission, Enstar revealed that total assets fell by around ten percent over the first half of the year, from $6.6 billion to $6.03 billion, while total liabilities also dipped from $4.92 billion to $4.34 billion.