Bermuda-based Aspen Insurance has exercised a 15 percent over-allotment option to purchase an additional 1.57 million shares, after it went public on the New York Stock Exchange.

This move completes the company?s ordinary share offering with a total of 12.1 million shares being sold with net proceeds for Aspen of approximately $245.5 million.

All in all, Aspen ? which was set up last year on the Island, but writes the majority of its business in London ? said it intended to use the proceeds from the offering to bolster capital for its subsidiaries, to pay down debt under its revolving credit facilities and for business costs.

Aspen, a property and casualty reinsurance company, was formed with initial backing from several investors including Wellington Underwriting Plc and Bermuda-based Montpelier Re.

All of the senior executives at Aspen actually moved to the company from top jobs at Wellington.

With them, they took 36 staff but senior management said this was all done with the ?complete blessing? of Wellington who agreed that Aspen would take on its property and casualty lines and its UK operations. Wellington?s stake in Aspen after the IPO went down to 16.7 percent holding in the company, worth ?146.5 million or $252.5 million, based on the $22.50 pricing.

The stake is worth 30 pence a share for Wellington, the company said in a Press statement. redit Suisse First Boston and Goldman Sachs Group Inc. managed the Aspen sale, sharing fees of $16.6 million with Deutsche Bank Securities Inc., UBS AG, Dowling & Partners Securities LLC, Fox-Pitt Kelton and Keefe, Bruyette & Woods Inc.

The next to launch its shares from Bermuda, and most likely on the London Stock Exchange, should be insurance company Catlin.