FY2025 obligations by the NAICS code on the award
67% of the $975.3M obligated under AC31 in FY2025 went to awards coded NAICS 541712.
- 541712 Research and Development in the Physical, Engineering, and Life Sciences (except Biotechnology)not in NAICS 2022$651.4M
FY2025 federal contract obligations, USAspending.gov
PSC AC31 is basic research coded to the defense-related activities subfunction, the third leg of the National Defense budget function alongside DoD military and atomic energy defense. FY2025 obligations were $975 million.
A retired NAICS code holding two-thirds of it
$651 million, about 67 percent, sits under NAICS 541712, Research and Development in the Physical, Engineering, and Life Sciences (except Biotechnology). That code was superseded in the 2017 NAICS revision by the 541715 series. Physical, Engineering, and Life Sciences R&D (541715) itself takes only $172 million here. Compare AC11, the DoD military basic research code, where the current code leads comfortably. The difference is a good proxy for contract age: AC31's money is running through older awards. Engineering services 541330 adds $80 million, 336992, Military Armored Vehicle, Tank, and Tank Component Manufacturing, adds $19 million, and 541511 adds $16 million.
PSC against NAICS, once
The PSC comes from the contracting officer and describes the purchase; the NAICS code also comes from the contracting officer and describes the industry of the work.
Both classification systems get revised, on different schedules, which is why a current PSC can pair with a superseded NAICS code on the same award.
PSC AC31 FAQ
What does PSC AC31 cover?
Basic research funded under the defense-related activities subfunction of the National Defense budget function, distinct from DoD military and atomic energy defense research.
What NAICS codes win AC31 work?
NAICS 541712 took $651 million of $975 million in FY2025, about two-thirds, with Physical, Engineering, and Life Sciences R&D (541715) at $172 million and Engineering Services (541330) at $80 million.
Why is a superseded NAICS code the largest here?
NAICS 541712 was replaced in the 2017 revision, but obligations continue against awards made under it. A high share of retired codes usually indicates long-running contracts, not new competition.
How does AC31 differ from AC11?
Both are basic research. AC11 is the DoD military subfunction and AC31 is defense-related activities, a much smaller budget category whose R&D coding practice varies more across agencies.