NEW YORK 13 (Bloomberg) - Assured Guaranty Corp. rose after Moodys Investors Service lowered its insurance financial strength rating by one level.

Assured is pleased that Moodys assigned a rating that connotes significant financial strength in today's economic environment, Dominic Frederico, CEO of the bond insurer, said on Friday in a statement distributed by Business Wire.

Assured rose $3.84, or 21 percent, to $21.94 as of 10.01 a.m. in composite trading on the New York Stock Exchange.

Moodys downgraded Assured to Aa3 from Aa2, the New York-based ratings company said in a statement on Thursday.