http://www.tax.state.ny.us/pit/incom...nformation.htm
You must file Form IT-203 if you:
*were not a resident of New York State and received income during the tax year from New York State sources, or
* moved into or out of New York State during the tax year.
This one explains it pretty deep for individuals
http://www.tax.state.ny.us/pdf/publi...come/pub88.pdf