FAR 52.219-14
Limitations on Subcontracting
What it says
On set-aside awards, caps how much of the contract value can flow to subcontractors that are not similarly situated. For supplies (other than acquisition from a nonmanufacturer), the awardee cannot pay more than 50% of the amount paid by the government to firms that are not similarly situated.
Why it matters on DIBBS
If you plan to source the item from another manufacturer, check this clause plus the nonmanufacturer rule before quoting — a set-aside win can be undone by a compliance problem here.