[CFA入门] Level 2 请教Soft Dollar Standards里的一段话，没看明白 公司, fiduciary, principal, research, accounts

allenxia

在notes 的94页，
In the case of principal trades not subject to other fiduciary regulations, the research may benefit other client  accounts, as long as disclosure is made to the client and prior permission is received.

什么是principal trades？能给个例子吗？这句话是否说，只要是principal trade的钱，公司就可以用这些钱去benefit other client accounts吗？谢啦！