Experiments are not permitted under this subpart and a conventional experimental radio license is required when:

(a) An environmental assessment must be filed with the Commission as required by § 5.63(a), or

(b) An orbital debris mitigation plan must be filed with the Commission as required by § 5.64, or

(c) The applicant requires non-disclosure of proprietary information as part of its justification for its license application; or

(d) A product development or a market trial is to be conducted.