47 CFR 25.289: Protection of GSO networks by NGSO systems.

(a) Unacceptable interference. Unless otherwise provided in this chapter, an NGSO system licensee must not cause unacceptable interference to, or claim protection from, a GSO FSS or GSO BSS network.

(1) An NGSO FSS licensee operating in compliance with the applicable equivalent power flux-density limits in Article 22, Section II of the ITU Radio Regulations (incorporated by reference, § 25.108) will be considered as having fulfilled this obligation with respect to any GSO network.

(2) [Reserved]

(b) Coordination. GSO and NGSO satellite operators must coordinate in good faith the use of commonly authorized frequencies in the 10.7-12.7, 17.3-18.6, or 19.7-20.2 GHz bands in the United States.