MAS Refresh 31 (April 2, 2026) introduced parallel but different requirements for SIN 339940OS4 and SIN 339940 - and both require action before May 7, 2026.
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What changed across both SINs?
- Removal of the 80/20 rule
- Clearer definition of “office products”
- Expanded identification of out-of-scope items
- Removal of redundant and outdated language
Bottom line: Scope enforcement is now stricter and fully contractor-driven
SIN 339940OS4 – More administrative work
You must:
- Complete and submit updated Letter of Compliance + Business Rules (T&C mod)
- Keep all awarded terms unchanged (fees, delivery, discounts)
- Submit a Delete (DEL) mod to remove out-of-scope items
SIN 339940 (non-OS4) – No T&C update, but still action required
Key difference:
- Letter of Compliance is removed
- Replaced by guidance: “Office Supply Definition and Examples per Category – Refresh 31”
You must:
- Review the new guidance resource
- Submit a Delete (DEL) mod to remove out-of-scope items
Deadline: May 7, 2026
Failure to comply may lead to contract cancellation under GSAR 552.238-79.
What this means operationally
- No more “buffer” from the 80/20 rule – every item must be in scope
- Keyword lists are only a starting point, not a full validation
- Expect higher risk of robomod actions if cleanup is incomplete
- Catalog governance and pre-mod validation are now critical controls
Question for contractors:
Are you running a full catalog scrub against scope – or relying only on GSA’s keyword list?
