The folowing is cited from: http://files.lsba.org/documents/Diversity/JonathonGrodearticle.pdf
TN (NAFTA Professionals)
The North American Free Trade Agreement (NAFTA) signed in 1994 by President Clinton established a visa category for citizens of Canada (TN-1) and Mexico (TN-2) engaged in business activities at a professional level. The regulations provide an exhaustive list specific occupational categories that qualify for TN status. See 8 CFR §214.6(c) The TN visa classification is employer and occupation specific and requires sponsorship by a United States employer. If, after a merger or acquisition, the successor company qualifies as a successor in interest of the prior company, then new petitions are not required. Here, counsel does not need to be concerned with the nationality of the new owners of the company, as the visa is linked to the nationality of the worker, not the company.
