Karl Rove has been utilizing the 501(c)(4) tax exempt form and status granted by the IRS to keep his donors safe and secret from public knowledge. All the meanwhile he's been using his group to persuade and influence political elections putting essentially all of his money into politics from the group. That is something the 501(c)(4) does not allow as a 501(c)(4) group can not spend more money on politics than what the 501(c)(4) is supposed to be for, that is:
(a) social welfare organizations, defined by statute as civic leagues or organizations operated exclusively for the promotion of social welfare; and (b) local associations of employees of which the net earnings are devoted exclusively to charitable, educational, or recreational purposes.
Please investigate Karl Rove's group.