You mechanic isn't operating in a regulated industry in most cases, these brokers are. You get what you pay for. You chose a cut-rate broker which clearly states in their policy that they reserve the right to pass along cost increases. The DTCC leaned on Penson to to charge these fees on the SELLING of unregistered, low volume securities. Seeing how you chose to trade with a low-rate broker, which also happens to have poor customer service, you weren't informed of the regulatory changes going on - but that's doesn't exclude you from having to pay said fees.
The simple fact is you chose a cut-rate broker. The burden is always on the traders to know the regulatory fulls. If you had chosen an actual full-feature broker, your broker likely would have done a better job communicating the regulatory changes to you - although it is not their responsibility. FINRA and the SEC clearly state the trader needs to stay abreast of changes. That's what you get for choosing a shitty broker - you shifted the burden of staying informed to yourself in lieu of low fees.
The only thing i see is you whining because you chose a broker that provides low customer service satification, instead of full-feature firm which could have helped you stay informed of the changes occurring in the market.
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