VMI and Consignment Are Different Inventory Decisions

Vendor-managed inventory and consignment are often mentioned together, but they answer different operating questions. VMI concerns who uses inventory and demand data to manage replenishment. Consignment concerns how possession, ownership, consumption, and settlement are recorded under an agreement. A company can use either model alone, combine them, or use neither.

That distinction matters for spare parts. If the replenishment owner, stock owner, and payment trigger are inferred from a label, shortages and financial discrepancies can stay hidden until a count, return, or program exit. The broader bulk-parts sourcing guide covers supplier and volume choices; this framework focuses on the operating records needed after a part scope is selected.

Answer two separate questions before naming the model

First ask who controls replenishment. Who receives on-hand, demand, open-order, and forecast data? Who sets the policy or proposes quantities? Who converts a proposal into an approved request or order, and who may override it? Oracle's 26B VMI documentation describes VMI through supplier involvement in inventory planning and replenishment creation. That software model illustrates the decision loop; it does not decide ownership or prove a universal VMI design.

Second ask who owns stock at each event. Identify the party that possesses the goods in transit, on receipt, in storage, after issue, and after any return. Name the event that changes the ownership record and the separate event that creates an invoice or payment obligation. Oracle's 25C consigned-inventory documentation explicitly distinguishes possession from ownership in its configured process and connects consumption advice with settlement. Actual legal title, risk of loss, tax, and accounting treatment require the governing agreement and qualified review.

Place the proposed arrangement in a two-axis map:

Replenishment control	Buyer-owned inventory	Supplier-owned inventory before agreed transfer
Buyer managed	Conventional buyer planning and buyer-owned stock	Buyer calls off or requests stock held on consignment terms
Supplier managed	VMI replenishment serving buyer-owned stock	VMI combined with consignment

The label cannot select the quadrant. The agreement version, approved transaction design, system configuration, and actual records must agree. If any ownership or payment event is unknown or contradictory, mark it open rather than inferring it from “stock at site,” “supplier managed,” or “consignment.”

Define the replenishment data and decision loop

Begin with the part numbers, revisions, storage locations, and sites in scope. Define on-hand, available, reserved, quarantined, damaged, and in-transit quantities. A supplier should not treat all physically present stock as available when some is held for inspection or assigned to another demand.

List each data field, system of record, owner, unit of measure, location and status code, timestamp, refresh frequency, and correction path. Include demand or consumption history, open orders, in-transit quantities, forecasts and revisions, and the policy inputs used for replenishment. Name who owns minimum and maximum settings or another policy, and how criticality, emergency need, pack size, capacity, and lead-time constraints enter the decision.

The current SAP Supplier-Managed Inventory documentation describes supplier-managed inventory through supplier determination of replenishment need using buyer-location data, and recognizes consigned VMI as a combined process. This supports keeping the two concepts distinct. It does not show that every VMI program includes consignment.

Separate a supplier proposal from an authorized order. Define who approves a replenishment request, how the supplier acknowledges it, what version controls, and what happens when the buyer overrides or freezes the plan. GS1 UK's order-message guideline includes a VMI example in which the supplier determines replenishment and transmits an order copy to the buyer. Treat that as a stable message-flow example, not a mandatory modern format or ownership rule.

Set exception rules for stale or incomplete data, unexplained spikes, negative available balance, duplicated messages, unit conversion, and loss of system access. Protect access credentials and limit data visibility to the agreed scope. Review forecast and replenishment performance, but do not assume VMI prevents stockouts or reduces inventory. Those outcomes depend on demand, lead time, capacity, data quality, and disciplined execution.

Define possession, ownership and settlement events

Draw an event flow from shipment through receipt, storage, issue or consumption, ownership transaction, invoice, payment, return, and correction. At every step record physical location, custody, condition, and the owner shown in the agreed ledger. A receipt into the buyer's warehouse can be separate from an ownership transfer.

Define consumption precisely. It may be a recorded issue to a work order, installation, scan, backflush, or another agreed transaction. Specify the system, timestamp, lot or serial link, approval and correction process. Oracle's 26B consigned-consumption documentation illustrates physical movement and ownership change as separate configurable transactions, including lot or serial selection. A real arrangement must use its own contract and controls.

Keep the commercial event explicit. Name what creates consumption advice or an equivalent record, what creates an invoice, the pricing date and basis, and how the parties reconcile the statement. The legal, tax, duty, accounting, and revenue-recognition owners should review their fields. An operating matrix must not decide those questions for them.

Plan corrections and reversals. If an issue is posted against the wrong part, lot, site, or owner, the corrected event should preserve the original record, authorization, reason, and resulting balances. Define returns before consumption separately from returns after the ownership record has changed. Period close should reconcile physical, buyer, supplier, consumption, invoice, and payment records without silently netting unexplained differences.

Reconcile counts, damage, loss and obsolete stock

Agree the count scope, frequency, method, observers, tolerances or investigation triggers, and ownership-separated report. Count by part, revision, lot or serial where required, location, condition, and owner. Exclude or separately identify quarantine, reserved, damaged, in-transit, and unprocessed return quantities.

For each positive or negative adjustment, preserve the pre-count balance, physical result, transaction history, evidence, investigation, approval, and posting. A physical shortage should not be posted as buyer consumption merely to force the records to balance. It may arise from transaction timing, mislocation, unit error, damage, loss, theft, or another cause that needs the agreed exception process.

Define how damage, corrosion, storage deterioration, loss, and suspected theft are contained and investigated. Identify the parties that review insurance and risk-of-loss terms; do not infer liability from custody or ownership labels. Finance handles credit, debit, and accounting entries under approved evidence. Warehouse or system users should not create a financial conclusion through an inventory adjustment.

Slow, obsolete, discontinued, or superseded stock needs its own status. Record remaining demand, engineering revision, alternate use, shelf-life or condition limits, open replenishment, and proposed return, transfer, buyout, or disposal route. Each action requires its stated authority. Do not scrap, write off, or return supplier-owned stock because a planner believes it is no longer needed.

Test fit on a limited spare-parts scope

A pilot should test whether the data and controls work for selected parts and sites. Review criticality, demand intermittency, lead-time variability, unit value, bulk and storage burden, pack size, revision and fitment risk, corrosion or shelf-life concerns, and lot or serial traceability. Frequent standardized fasteners present a different operating problem from high-value, slow-moving rollers with sporadic demand.

Audit data completeness and latency before giving a supplier replenishment responsibility. Confirm receiving and count discipline, supplier planning capacity, capacity constraints, emergency communication, and the service target the parties actually intend to monitor. Record baseline stock, shortages, expedites, forecast error, count accuracy, and transaction latency using agreed definitions; avoid generic savings percentages.

Choose a small SKU and site scope, training plan, system-access boundary, support owner, exception simulation, review frequency, and go/no-go criteria. A pilot can reveal that replenishment data are workable while consumption records are not, or that consignment reconciliation works without supplier planning. Those are different findings. Nothing on KTSU's public site establishes that it offers VMI, consignment, local stock, or data integration, so a buyer must discuss actual capability and terms directly.

Plan exit, handover and final reconciliation

Define expiry, termination, site closure, part discontinuation, supersession, or supplier-change triggers before the program begins. Name the last replenishment cutoff, how open orders and in-transit shipments are treated, and when data access ends. Preserve records and remove credentials through the approved access process.

At exit, count on-hand stock by owner, condition, location, lot or serial, and status. Reconcile unused consigned quantities, buyer-owned quantities, consumed but unreported items, invoices, returns, and open discrepancies. Return, transfer, buyout, or disposal options depend on the agreement and authorized commercial, legal, tax, and accounting review. The framework does not set a price or assign termination liability.

Record obsolete or superseded stock, final statements, approvals, archive location, successor process, and unresolved items with owners. Do not close the program while the physical count, buyer ledger, supplier statement, and consumption advice show different quantities.

Use the responsibility matrix to expose three states

Activity or event	Normal	Missing	Conflict
Replenishment	Supplier uses timestamped agreed data; buyer authorization and acknowledgment align	Forecast exists but policy owner or approved order is absent	Supplier request and buyer order show different part, revision, unit, or quantity
Possession and ownership	Location and owner are recorded before and after each agreed event	Ownership-change event or governing agreement is not identified	Physical custody is treated as proof of title despite a different ledger
Consumption and settlement	Issue, consumption advice, invoice, and payment trace to the same item and quantity	No consumption definition, payment trigger, or correction process	Supplier statement and buyer transactions show different consumed balances
Count and exception	Physical and system balances reconcile by owner and condition	Damage, loss, or obsolete-stock route has no owner	Shortage is posted as consumption solely to force balance
Exit	Cutoff, on-hand stock, open orders, returns, records, and final approval reconcile	Data-access end or unused-stock path is undefined	Program is marked closed while stock and financial records disagree

Use each row to record the supplier role, buyer role and approver, data source and frequency, possession, owner before and after the event, payment trigger, evidence, impact, next action, and closure owner. A missing field remains open. A conflict stops the affected transaction or conclusion until the authorized parties resolve it.

A sound design can therefore say exactly who replenishes, who approves, who possesses, who owns, when consumption is recorded, and how exceptions close. It does not need to pretend that VMI and consignment are synonyms, or that an inventory label has settled the legal and accounting terms.