Either way you've lost 1%, but you can decide whether to hold the upside exposure and voting control.
I think the key is the size of the fine. $1B to JPM is not really a whole lot. Maybe scaling the fine according to the size of the entity might make sense, but then there's a question of why everyone else at JPM is getting fined simply for doing their job in the same building as the guys who did this.
Edit. On second thought I guess you mean there will be a restriction on buying back the shares?
Shareholders can change corporate behavior lik Carl Icahn but here it seems like it was very opaque to even monitor, the other way they can enforce good behavior is to sell the stock.
https://en.m.wikipedia.org/wiki/Activist_shareholder
The sibling comments have an interesting worldview: can't fine management cause it's not their firm, can't fine shareholders cause it's not their fault, its nobody's fault.
That's the role of shareholders AFAICT, to hold their board and the company accountable. Fail to do so and lose your shareholding seems the right direct risk.
The fines could also be a lot larger, because there is minimal risk of bankrupting a business from diluting existing shareholders. A 1% shareholder hit would be $4B at current market cap. Make it 5% and really make shareholders pay.