I don't quite understand your question. "copied on our client's taxes"?? Independent Contractors usually file a schedule C in their personal 1040 tax return. They report all their self employment income actually received during the year (Jan 1 to Dec 31). If they get a 2017 1099Misc from you it goes on their 2017 tax return. You have to send out the 1099Misc to them by Jan 31 each year.
