Most PAC explainers stop at the definition. The interesting part is the strategy on both sides: how buyers use PAC legitimately (and where audit risk starts), and how sellers position products so PAC demand finds them — a topic almost nobody wTPA about, which suits the sellers already benefiting just fine.
Public procurement defaults to brand-neutral competition — specs published, all compliant brands compete. PAC is the sanctioned exception: when the requirement genuinely needs this article (compatibility with installed systems, validated scientific equipment, spare parts for an existing fleet, standardization already in place), the buyer certifies that proprietary need — the Proprietary Article Certificate — with justification and approvals per procurement rules, and procures the named product.
PAC bid/buying on GeM: the PAC route appears in GeM's flows as PAC-marked procurements (you'll meet "pac bid in gem" in bid lists) — participation is effectively scoped to the named brand's chain: the OEM and its authorized resellers.
Legitimate Grounds: Cluster around genuine non-substitutability: OEM spares for installed equipment, reagents/consumables validated for specific instruments, compatibility-locked additions to existing systems, and standardization decisions formally taken.
Audit Attention Risks: PACs whose justification reads as brand preference dressed up — "we like this one" in certificate form — trigger strict scrutiny. Buyers must treat the justification file as protection and write it as if an auditor will read it (where PAC sits among purchase routes).
Install Base = Future PAC Gravity: Every instrument, system or fleet you place creates downstream demand — spares, consumables, compatible expansions — that may legitimately qualify as proprietary need.
Design for Legitimate Lock-in: Validated consumables, calibration/service ecosystems, and documented compatibility build value that makes your article genuinely non-substitutability, not artificially so.
Make PAC Easy to Justify: OEMs who supply buyers with technical documentation of non-substitutability (compatibility matrices, validation records) lower the buyer's paperwork cost of doing the right PAC — and win renewals.
Keep the Chain Ready: PAC procurements still execute through GeM — your catalogue, your resellers' current authorizations, and your panel hygiene decide whether PAC demand converts smoothly.
For OEMs in equipment/scientific/systems categories, PAC-positioning ranks among the most under-used strategies on the platform — mostly because sellers meet PAC as vocabulary, not as a business model.
| Metric | Open bid | PAC purchase |
|---|---|---|
| Competition | All compliant brands | The named article's chain |
| Basis | Published specs | Certified proprietary need |
| Seller's lever | Price + qualification | Install base + non-substitutability |
| Risk profile | Competitive squeeze | Buyer-side justification scrutiny |
Format & Issuance: It's a buyer-side certificate (the procuring entity certifies proprietary need per its approval hierarchy) — sellers don't issue PACs; they earn being named in them.
Certificate Requested in ATC vs PAC: Different things entirely. ATC certificate demands are bid-document requirements on sellers, whereas PAC is the buyer's procurement-route justification.
PAC Full Form in GeM Portal: Proprietary Article Certificate — now you know more than just the definition.