A.M. Best Co. has affirmed the issuer credit rating (ICR) of “bbb” of American International Group, Inc. (AIG) (New York, NY (NYSE:AIG). Concurrently, A.M. Best has affirmed the financial strength rating (FSR) of A (Excellent) and the ICRs of “a” of the members of the Chartis U.S. Insurance Group (Chartis US) and the members of the Lexington Insurance Pool (Lexington) (both headquartered in Boston, MA). At the same time, A.M. Best has affirmed the FSR of A (Excellent) and the ICR of “a” of American International Reinsurance Company Ltd. (AIRCO), a Bermuda-domiciled reinsurer. The outlook for the ratings above is stable. In addition, A.M. Best has affirmed the FSR of A (Excellent) and the ICR of “a” of AIU Insurance Company (AIUI) (New York, NY). The outlook for these ratings is negative. (See below for a detailed listing of the companies and ratings.) The ratings for the members of Chartis US reflect its supportive level of risk-adjusted capitalization, generally solid operating earnings and its leadership position in the global commercial lines insurance market. Offsetting rating factors include the effect of soft market conditions on the group’s recent underwriting and operating results, A.M. Best’s expectation of continued adverse development of prior years’ loss reserves and the group’s exposure to natural and man-made catastrophe losses. Chartis US has historically demonstrated an ability to produce favorable operating results despite variability in its underwriting performance; however, this ability has been challenged in recent years. The stable outlook reflects AIG’s position in the U.S. commercial market; its ability to lead, attract and retain clients by leveraging its significant global capacity, extensive product offerings and innovation; as well as its greater emphasis on technical pricing and predictive modeling. While reserve development remains a concern, the stable outlook suggests that any future reserve development will be within a level acceptable to A.M. Best. A.M. Best also expects that the group will continue to maintain a supportive level of risk-adjusted capitalization through favorable net earnings while providing shareholder dividends to its parent in accordance with historical norms.