The ratings agency kept its long-term rating for the Japanese economy, which it had downgraded in January, unchanged at AA-minus.
Fitch Ratings downgraded AIG's long-term rating to AA+, Moody's Investors Services amended its recommendation from stable to negative and Standard & Poor's placed the company and its subsidiaries on credit watch.
The long-term rating remains a notch below the ratings agency's top grade.
Fitch Ratings downgraded the firm's long-term rating to A from A with a "negative outlook".
Fitch Ratings on Thursday assigned a long-term rating of BBB to Capmark Financial, near the low end of investment grade.
Of the other major ratings agencies, Fitch has a long-term rating of A for Clydesdale, with a stable outlook, while Standard & Poor is at BBB+, with a negative outlook.
Now the ratings agency has lowered its sovereign, long-term rating on Spain to AA+ from AAA, citing structural weaknesses in the Spanish economy.
But the ratings agency also said that BHP's long-term rating was unlikely to fall below A2, from A1 now.
Accenting that concern, Standard & Poor's, the credit ratings agency, on Tuesday cut Italy's long-term rating a notch to BBB, just two steps above "junk" status, citing the country's falling economic output and weakened financial system.
It also cut Goldman Sachs's short-term ratings to A-1 from A-1+, and affirmed its A+ long-term rating.
The ratings dropped to AA+ from AAA, in lockstep with its long-term rating for the United States.
