Mutilated currency is currency which has been damaged – to the extent that: (1) one-half or less of the original note remains; or (2) its condition is such that its value is questionable. Currency notes can become mutilated in any number of ways. The most common causes are fire, water, chemicals, and explosives; animal, insect, or rodent damage; and petrification or deterioration by burying.
What is not considered mutilated currency?
Unfit currency for redemption is currency which is unfit for further circulation because of its physical condition such as dirty, defaced, limp, torn, or worn. Unfit currency should not be forwarded to Bureau of Engraving and Printing for redemption, but may be exchanged at commercial financial institutions.
The BEP can still accept them, but I'm curious if BofA is actually doing this and if it'll stand up. More FAQ's can be read here