Can he do an unpaid internship on K1?

If the K1 holder does not have the temporary work stamp in their passport or a valid EAD, then they cannot do any work in which a US citizen can be paid for. Even though it is an unpaid internship, if they are doing duties which someone can be paid for...(ie, an unpaid intern in an office might answer phone calls....even though they are not being paid, a US citizen COULD be paid to do this, therefore this is not allowed without the correct work authorization), then no, they can not legally be an unpaid intern. The kind of unpaid work you could do without this authorization is stuff like serve food in a soup kitchen etc.
 
Even though it is an unpaid internship, if they are doing duties which someone can be paid for...(ie, an unpaid intern in an office might answer phone calls....even though they are not being paid, a US citizen COULD be paid to do this, therefore this is not allowed without the correct work authorization), then no, they can not legally be an unpaid intern.

It depends on the role itself. If there are other interns doing the same work unpaid, then it is likely to be kosher.
 
It depends on the role itself. If there are other interns doing the same work unpaid, then it is likely to be kosher.

Even if the role if kosher and there are 10 interns, it could still be perceived that such work 'could' be done by a paid US citizen. The K1 does not allow for 'work' per se without authorization (I actually take back my comment about the work stamp in the passport as this is now worthless), just as in the same way someone could not come over on a tourist visa and do an internship. There are specific visas which allow for unpaid internships (ie, J1), but unfortunately, the K1 is not one of them. The chances are the person in question could get away with it as it is unlikely that there would be an ICE investigation at wherever the internship is taking place, however, I personally would not take the risk.
 
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