Clawbacks on Wall Street? Easier said than done.

Bank analysts believe much of the pay claimed by now-departed Wells Fargo executive Carrie Tolstedt can't be taken back, regardless of how much noise Capitol Hill legislators make. Tolstedt was the head of the Wells Fargo consumer banking unit that's at the center of institution's fake accounts scandal.

For one: stock Tolstedt bought, which was not part of her compensation agreement, can't be clawed back, said Rafferty Capital Markets banking analyst Dick Bove. It's unclear how much of Tolstedt's paper gains were made from stock that she owned, but the executive departed Wells Fargo after retiring with a little under $100 million in overall stock and options from her career.

And that designation — retired, rather than fired — will make all the difference going forward.

"They did not fire her for cause," Bove noted, when asked about how the bank could go about executing clawbacks. "They have to come up with a reason she did not perform her function."