A1(redirected from BCL2-related protein A1)
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A subset of the third-highest bond rating by Moody's. The other subsets are A2 and A3, both of which are slightly lower. Bonds with an A1 rating are investment-grade, meaning that banks are allowed to hold them. Bonds with A1 ratings are low-risk and low-return, though not as much as Aa and Aaa ratings. The rating is equivalent to the A+ rating by S&P and Fitch.