48 C.F.R. § 270.102 – Policy.

(a) The contracting officer may only award one sole-source, follow-on contract to the incumbent contractor if—
1. (1) The contractor has represented that it is a qualified business; and
2. (2) The contract is for the continued development, production, or provision of products or services that are the same as or substantially similar to those procured under the prior contract awarded to the contractor by or for DoD.
(b) The contracting officer shall justify the use of a sole-source contract in accordance with FAR 6.303 and 6.304 and cite FAR 6.302-5 as the exception to full and open competition.