Are trades (and business expenses) done prior to a newly formed LLC or tax shelter gone with the wind or can they be incorporated into a newly created tax shelter? Not sure if this question is extremely vague or completely clear. Hopefully you understand the gist of my question.
Not if they occurred before the entity was formed. BTW, if you're in the U.S. an LLC isn't a tax shelter and has minimal impact on your taxes beyond allowing you to deduct some expenses and potential form an IRA. There really aren't any legal "tax shelters" except for IRAs for trading profits in the U.S.