By Outrider Editorial Team · Updated August 20, 2026
PSC AC61 belongs to the pre-2020 R&D code structure, where A-series codes were organized by defense system type rather than by budget function. It does not appear in the current PSC Manual. In October 2020 the government end-dated 721 R&D PSCs and activated 155 replacements built on the budget-function and stage model used by AC11 through AC35. AC61 still recorded $850 million in FY2025.
A fossil in two classification systems at once
Effectively all of it, $851 million, sits under NAICS 541712, itself superseded in the 2017 NAICS revision. The remaining registrations are negligible: 336411 at $560 thousand, 611310 at $76 thousand, 541710 at $0, and 336419 at $0. Note that the leading NAICS total slightly exceeds the code total, because FY2025 also booked net de-obligations elsewhere in the code.
PSC and NAICS, briefly
Both systems label an award, one describing the purchase and one describing the seller, and both were revised while these awards stayed open.
This is a data hygiene problem, not an opportunity. A retired PSC paired with a retired NAICS code and near-total concentration in a single registration means one or two long-running research relationships, not an addressable market. If AC61 appears in your pipeline analysis, treat it as history and search the AC1x, AC2x, and AC3x series instead.
NAICS crosswalk
Where FY2025 AC61 dollars landed, by the winning vendor's registered NAICS code.
- 541712Research and Development in the Physical, Engineering, and Life Sciences (except Biotechnology)$850.5M
- 336411Aircraft Manufacturing$560.1K
- 611310Colleges, Universities, and Professional Schools$76.0K
- 541710Research and Development in the Physical, Engineering, and Life Sciences$0
FY2025 federal contract obligations, USAspending.gov
Frequently Asked
PSC AC61 questions, answered.
What does PSC AC61 cover?
Basic research on defense system electronics and communication equipment under the pre-2020 A-series structure, which organized R&D by defense system, not by budget function. The code was end-dated in October 2020.
What NAICS codes win AC61 work?
NAICS 541712 accounts for essentially the entire $850 million recorded in FY2025. All other registrations are under $560 thousand combined.
Why is a retired PSC still showing obligations?
Fiscal-year obligation totals are transaction-level and include modifications and de-obligations booked against awards signed under the earlier code set. The award keeps its original PSC for life.
What replaced the AC6x codes?
The budget-function and stage structure activated in 2020: AC11 to AC15 for DoD military, AC21 to AC25 for atomic energy defense activities, and AC31 to AC35 for defense-related activities.
Watch AC61 opportunities
Solicitations are filed by PSC as well as NAICS. Outrider matches your company profile against both so nothing filed under a code you do not watch slips past.
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