If an individual is on a B-1 visa, can they earn money in the US?

An individual on a B-1 visa is primarily in the United States for business purposes, which generally does not include earning money through employment or self-employment in the U.S. The B-1 visa permits activities such as attending meetings, conferences, negotiating contracts, or engaging in other legitimate business activities. However, it does not authorize the holder to work or earn income from a U.S. source.

In this context, the correct rationale is that individuals holding a B-1 visa are prohibited from engaging in any form of employment that generates income while in the United States. Earning money in the U.S. would typically require a different visa classification that permits work, such as an H-1B or a work visa. The assertion that they cannot earn money aligns precisely with the official restrictions placed on B-1 visa holders.