Hello, my name is XXXXX XXXXX U.S. immigration and business
attorney, and I'll be happy to answer your questions today.
You stated that you have an intern currently training at your company, and that you'd like him to continue interning until his OPT is approved. The answer to your question is "Yes," that student may continue interning until his OPT is approved.
Usually, if an internship is truly voluntary, and involves no form of compensation, than a student can volunteer without having to file any paperwork with the USCIS at all. However, if the student will be provided with any stipend or compensation during the training period, then he will have needed to receive USCIS approval before even beginning the training period with your company.
Once that student receives his Employment Authorization Card (EAD), you'll be able to see the dates he is authorized to work in the U.S. You should not pay your intern a salary, or start accruing working hours, until the first date on that card has arrived.
For post-graduation OPT, a student must be employed for at least 20 hours/week. Training your intern more than 20 hours/week in an official capacity may suggest that he is already "working" for your company, so try to limit your intern's training hours to less than 20/week, until his work authorization has been approved.
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