Hello I am planning to set up an online business that earns with advertisement as an LLC (probably in Delaware) with pass-through taxation. I am neither a US citizen nor a US-resident living in Europe. Many of my clients are from the US and there are also some freelancers working for the company who live in the US. The company would have no employees who are US-residents and the management of the company would be in Europe. My question is to what extent I or the LLC would have to pay taxes in the US (federal or state) if at all? It appears to be dependent on the definition of the term "doing in business in the US". Thus it probably boils down to the question whether having clients and freelancers in the US means that I or the company is doing business in the US. Any advice would be very much appreciated.