The official answer to this question is “absolutely not”. But, like the discussion last week, it is really not so clear cut. If you are on a B visa, you cannot come to the U.S., get a job, and start getting paid. However, there are other scenarios where “work” in some form or another can sometimes occur.
I have already discussed a minister coming to the US for an “evangelical” tour under which he is able to receive payment from collections to cover his expenses. This is not “work”, but he is receiving some money for his service.
A person can come to the US to participate in business or educational seminars. Can he get an honorarium if he presents? To be honest, I don’t know. I think it probably happens frequently. This is similar to the situation with a minister coming to the US for an evangelical tour and who is supported by offerings along the way, but the right to receive an honorarium is not specifically spelled out in the regulations,,
A person can come to the US to paint or to record a song or to measure a client for a suit or things like that, but the paintings and songs normally should be sold abroad, and the suit should be made abroad and paid for abroad (and then can be shipped to the US purchaser).
A person can come to the US to investigate an investment opportunity or to meet with potential clients or business partners or to repair equipment sold to an American by a foreign company. They can come to the US to observe a business so that they can learn how to do it in their home country. They can come to the US for a short time on behalf of a parent foreign company to work in the US at a foreign-owned company to do things like provide guidance to the US company. In all of these cases, the B visitor is here temporarily, being paid by a foreign company to perform services on behalf of the foreign company.
In general, the line seems to be that a person cannot be earning his wages from a US source or producing things to be sold in America — unless it is something temporary and specific like receiving offerings to defray the cost of travel during an evangelical tour. Doing occasional jobs for Americans for pay —- construction, shoveling snow, raking leaves, fixing cars, etc, for money is working for Americans, even if it is just “one time” type work, and is not allowable for someone on a B visa.
One thing that I am doubtful about is when a person is here on a B visa and works on-line for an employer in his home country. I think that no one would complain if a person is here on vacation, and goes on line to perform a quick service for his foreign employer. It gets more murky if the person is here on an extended B visa — perhaps for several months, and he regularly gets on line and works for an employer at home (or, perhaps, is self-employed but sells his on-line product in his foreign home country). I think that if a Border Guard knows that he is doing this, I think that the Border Guard would not allow the person in — after all, he is working, and he is in the US. However, I am not certain that this is in violation of the statute. The person is not working for a US company, he is not keeping a US worker from getting a job here, his work product is being sold in another country, and he is being paid in another country. This is a case where technology has passed the intended scope of the law. However, if you do something like this, you need to know that it might not be found to be acceptable.
I hope this is interesting and helpful. Remember that this is not legal advice. It is just a summary of certain aspects of immigration law which may or may not apply to your situation. I encourage you to consulate an attorney if you think any of this may apply to your situation.