What forms of use require extended licensing?
Use of the Web Font Software: (1) on workstations within your organization (with the exception of use solely for Permitted Internal Use on the number of Workstations indicated in a Professional Tier account), (2) as part of or in conjunction with any Application, (3) for Editing, or (4) in a Commercial Product, requires extended licensing. In addition, if you want to host fonts on your own server, extended licensing is required.