I read here: http://www.workpermit.com/us/employer_b1_b2.htm
/start quote
The following activities require a working visa, and may not be carried out by business visitors:
Running a business. "Gainful employment", Payment by an organization within the US, Participating as a professional in entertainment or sporting events,
/end quote
Wouldn't a startup count as Running a business?
I've read, A foreign national can easily start a business in US. But, B1 Visas doesn't seem to allow running a business. :Confused: