48 C.F.R. § 15.601
As used in this subpart-
Advertising material means material designed to acquaint the Government with a prospective contractor's present products, services, or potential capabilities, or designed to stimulate the Government's interest in buying such products or services.
Commercial product or commercial service offer means an offer of a commercial product or commercial service that the vendor wishes to see introduced in the Government's supply system as an alternate or a replacement for an existing supply item. This term does not include innovative or unique configurations or uses of commercial products or commercial services that are being offered for further development and that may be submitted as an unsolicited proposal.
Contribution means a concept, suggestion, or idea presented to the Government for its use with no indication that the source intends to devote any further effort to it on the Government's behalf.
48 C.F.R. §15.601