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