Section 915.605 - Content of unsolicited proposals(b)(5) Unsolicited proposals for nonnuclear energy demonstration activities not covered by existing formal competitive solicitations or program opportunity notices may include a request for federal assistance or participation, and shall be subject to the cost sharing provisions of subpart 917.70.63 FR 56851, Oct. 23, 1998, as amended at 74 FR 36364, July 22, 2009