If a Financial Advisor makes a mistake, does he or the firm have to pay for it?

If a Financial Advisor at a large firm like Merrill Lynch makes a mistake (buystoo much stock or sells too much stock for a client) and the mistake results in a loss to the firm, does the firm have insurance for such mistakes? Let's say I ask my broker to buy 1000 shares of Microsoft and he accidentally buys 100,000 shares. Furthermore, let's say he doesn't notice the mistake for 10 minutes or so and there's been significant movement in the stock resulting in a cost of $50,000 by the time he makes the correction. I know the client isn't on the hook but my question is wheather firms take out insurance for mistakes like these.