Maybe it was not a glitch. Remember, when a stock goes x dividend, it drops by the amount of the dividend.
However, with FNMA if shareholders were awarded an equivilant of $12 per share, that would bring the price to right at $12.63 (plus or minus a couple pennies) If you use 1.1 billion shares, that's damages of around 13 billion.
There would likely be some sort of "x date", that if you owned the shares on the day before "x date" you would get the dividend.
It follows that it was announced that current shareholders would get a 12 dollar dividend on (a date in the future), it would mean the shares were worth 12.00 more if it included this dividend. 'Its all a guess..an unsubstantiated one, but plausible.
Im not sure how much "per share" the price dropped when NWS was announced, but it had to be a whopper of a drop. Talk about disappointing earnings, how much would apple drop if the government announced the confiscation of all APPLe profits from now on? Probably more.