48 C.F.R. § 9904.420-30
(a) The following are definitions of terms which are prominent in this Standard. Other terms defined elsewhere in this Chapter 99 shall have the meanings ascribed to them in those definitions unless paragraph (b) of this subsection, requires otherwise.
(6) Independent research and development means the cost of effort which is neither sponsored by a grant, nor required in the performance of a contract, and which falls within any of the following three areas: