Where do you find information about the $400k limit? I searched the NFA website and I only see the 15 clients limit for exemption but not the $400k. Thanks.
This thread is old, but still interesting. Some of the comments just do not look right. Some brokers like IB and Schwabs offer a combined stock/futures account. You can trade both and FX, crypto etc. So you can't distinguish between stock and futures accounts. You can call yourself whatever you want, prop trader, money manager etc. and still stay unregistered, unless you take on outside money. If you manage your immediate family's money and receive compensation, I do not think that is considered income as a money manager. I do not think you need to registered as a CTA or RIA if you want to take 20% profit of the gains you make from your son's account. I'm not a lawyer. It is just my two cents.