LMDS licensees must make a showing of "substantial service" in their license area within ten years of being licensed. "Substantial" service is defined as service which is sound, favorable, and substantially above a level of mediocre service which might minimally warrant renewal. Failure by any licensee to meet this requirement will result in forfeiture of the license and the licensee will be ineligible to regain it.
47 C.F.R. §101.1011