1099 from broker; anyone know how to split one out? I've been trading for myself and two others.

Might ask here:

The Tax Thread I thought we could use a thread devoted to Taxes. This is all things taxes regarding trading. One example, Advantages/disadvantages for different situations (equities, futures, forex, etc) as well as benefits of filing sole-proprietor vs LLC or as a …

But the general answer is, you assumed all the tax liability unless you are an LLC or Corp (I believe). That said, you could just bill your friends.

Mike