48 CFR §2052.211-71

As prescribed at 2011.104-70(b), the contracting officer shall insert the following clause in all solicitations and contracts except firm fixed price or indefinite delivery contracts to be awarded on a time-and-materials or labor-hour basis, or which provide for issuance of delivery orders for specific products/serviced line items. The contracting officer may alter this clause prior to issuance of the solicitation or during competition by solicitation amendment. Insignificant changes may also be made by the contracting officer on a case-by-case basis during negotiation without amending the solicitation.