AIG was unable to pay back it's bailout. Treasury converted it's SPS to AIG common shares and then sold these shares. After the bailout was paid back, Treasury sold back the warrants it held. That was the standard offer for all recipients of the bailouts. The warrant buy back was valued at the individual corporation's average closing price for the prior 20 days.
Any day FHFA and Treasury decide to write down Fannie and Freddie SPS, they should be entitled to buy back their warrants at "fair value" which according to their warrant agreements is average closing price for prior 20 days.