Aspen Insurance Holdings Limited (AHL)

Aspen Insurance Holdings Limited is a Bermuda-based specialty insurance and reinsurance group that was founded in 2002, during a period of tight capacity in the property and casualty markets after the September 11 attacks. It is headquartered in Hamilton, Bermuda, and operates through underwriting platforms in Bermuda, London, the United States and other markets, including a Lloyd's syndicate.

The company writes insurance and reinsurance across specialty lines such as property, casualty, marine, energy, aviation, financial and professional lines, and property catastrophe and other reinsurance. Its customers are corporations, insurance companies and brokers around the world. Aspen's business is organized into an insurance segment and a reinsurance segment.

Aspen first listed on the New York Stock Exchange in December 2003 under the symbol AHL. In 2019 it was acquired by investment funds managed by Apollo Global Management in a take-private transaction, although several series of its preference shares remained publicly traded. Under private ownership the company reworked its portfolio and focused on underwriting profitability.

Aspen returned to the public markets in 2025 with a new initial public offering of its Class A ordinary shares on the New York Stock Exchange, again under the AHL symbol. It files annual reports on Form 20-F as a foreign private issuer. Its preference shares trading under symbols such as AHL-PD, AHL-PE and AHL-PF also appeared on the Form 25 filing.

In August 2025, only a few months after the IPO, Aspen agreed to be acquired by Sompo Holdings, a large Japanese insurance group, for about $3.5 billion. The agreement provided for $37.50 per share in cash for the company's ordinary shares. For Sompo, the transaction expanded its international property and casualty and reinsurance operations, including a larger presence in the United Kingdom and the Lloyd's market.

Sompo announced completion of the acquisition on February 24, 2026, and Aspen became part of the Sompo group, with plans to move the business to the Sompo brand. The NYSE listing was removed following the Form 25 filing on February 24, 2026. Sompo and Aspen indicated that the terms of Aspen's preference shares would remain unchanged and that they might later seek to redeem, repurchase or delist them.

The transaction illustrates the consolidation of specialty insurers and reinsurers by large global groups seeking scale and diversification. Aspen's common shares had therefore been public in two separate periods, from 2003 until the 2019 take-private and again from the 2025 offering until the Sompo acquisition. Holders of the ordinary shares received cash and no longer hold an interest in the company, while the treatment of the preference shares was addressed separately by the company.