The FAR is not the only rulebook in a solicitation. An agency head may issue, or authorize the issuance of, agency acquisition regulations that implement or supplement the FAR 1.
The Department of Defense's is the one most contractors meet first: DoD implementation and supplementation of the FAR is issued in the Defense Federal Acquisition Regulation Supplement, the DFARS 2. It is codified as chapter 2 of Title 48 of the Code of Federal Regulations 3.
Supplements are numbered to sit beside the FAR
Agency regulations are built to be read next to the FAR: they parallel it in format, arrangement and numbering system 4. In a FAR citation, the digits to the left of the decimal point are the part number 5.
Material with no FAR counterpart gets numbers of 70 and up 6. DoD-only numbers such as 204.7304 and 252.204-7012 follow that pattern.
One pair shows the pattern. FAR 44.403 tells the contracting officer when to insert the FAR clause on subcontracts for commercial products and commercial services 7. DFARS 244.403, the same number with a 2 in front of the part, prescribes DoD's own clause on that subject, 252.244-7000 8.
Finding the supplement clauses in your solicitation
In a uniform-format solicitation, clauses sit in Section I, which holds the clauses required by law or by Part 15 and any additional clauses expected in the resulting contract 9.
Each clause names the rule that put it there. FAR clauses open with a line such as "As prescribed in 19.708(a), insert the following clause" 10. DFARS clauses open the same way, for example "As prescribed in 204.7304(c), use the following clause" 11.
A supplement clause can add real work. DFARS 252.204-7012 requires the contractor to provide adequate security on all covered contractor information systems 12.
Worked example. Contractor G reads a solicitation from a defense agency and finds 252.204-7012 listed in Section I. It reads the clause, then the prescription at DFARS 204.7304(c), and adds the cost of the security requirements to its price.
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