What it means
Secured lending runs on priority: first to file usually wins. The purchase money security interest is the great exception, designed so new inventory can be financed even when old liens blanket everything.
A PMSI arises when credit enables the purchase itself: a seller financing goods on credit, or a lender advancing money that the borrower uses to buy the collateral. UCC Article 9 governs the system, and section 9-103 defines the purchase money security interest, distinguishing inventory, equipment, and consumer goods with different rules for each.
The superpriority is the prize: a perfected PMSI in inventory or equipment can prime an earlier lender's after-acquired property lien, letting new suppliers finance into an already-encumbered business. The conditions are strict and deadline-driven.
Inventory PMSIs require perfection before the debtor gets possession plus notice to earlier filers; equipment PMSIs allow a twenty-day window after delivery. The policy logic is pragmatic: without superpriority, a first lender's blanket lien would freeze the borrower forever, and no supplier could safely finance new stock.
Failure to follow the steps forfeits the privilege: a misfiled financing statement or a missed notice drops the PMSI lender back into the ordinary queue, a mistake discovered precisely at the worst moment. For a non-finance reader, a PMSI is the rule that lets the oven dealer repossess the oven it financed, even when the bank's lien claims everything in the bakery.
Practice turns on discipline at closing. Lenders run lien searches before advancing, suppliers calendar the twenty-day window at shipment, and everyone checks the financing statement against the debtor's exact legal name.
The consumer goods rule reflects deliberate simplicity. Filing systems would drown in appliance purchases, so attachment alone perfects, leaving garage-sale disputes to a special exception for second-hand buyers.
Cross-border deals add a translation problem. Other systems achieve similar ends through retention of title and hire purchase, and matching the concepts matters when collateral or financiers move between legal families.
The PMSI question arrives in every workout. When a borrower fails, the first spreadsheet lists who holds superpriority over which assets, and that ordering often decides who negotiates from strength.
In practice
Real-world examples.
Example
A machinery dealer finances a lathe for a small engineering workshop, files within twenty days, and primes the bank's blanket lien on that machine. The bank had lent against everything the workshop owned, but the dealer's timely filing put it first for that one asset. Twenty days made all the difference.
Example
An inventory financer lends to a bicycle retailer so it can buy a new season's stock. Before delivery it notifies the retailer's existing lender and files its financing statement, securing PMSI superpriority in the new stock. The earlier lender cannot claim those bikes ahead of the financer.
Example
A consumer buying a sofa on store credit gives the seller an automatically perfected PMSI with no filing at all. Filing systems would be swamped if every household appliance purchase needed a record. The seller can still reclaim the sofa if the buyer defaults, subject to the usual consumer protections.
Formula
Calculation
Perfect a PMSI in equipment by filing within 20 days of the debtor receiving possession; for inventory, file and notify earlier secured parties before the debtor receives possession. Consumer goods perfect automatically on attachment.
Worked example. A fictional bakery owes its bank $1,000,000 under a blanket lien. A dealer then finances $200,000 of ovens, which are delivered on 3 March.
- Filing deadline = 3 March + 20 days = 23 March. The dealer files on 15 March, so the PMSI is perfected in time.
- The bakery fails and the ovens are sold for $150,000. Because the PMSI primes the bank on those units, the dealer takes the full $150,000 first and the bank receives nothing from the ovens.
- The dealer's shortfall is $200,000 - $150,000 = $50,000, which it claims as an unsecured creditor. Had it filed on 25 March, day 22, it would have lost priority and the bank would have been paid first.Case study
Seen in the real world.
This case study is fictional and illustrative. A made-up restaurant group in Texas carries a bank loan secured by everything it owns, now and later. When a kitchen equipment dealer offers to finance $200,000 of new ovens, its counsel runs the PMSI checklist: security agreement signed before delivery, financing statement filed within twenty days of the ovens arriving, and the collateral described precisely as the financed units. Two years later the group fails, and the bank claims all equipment under its blanket lien.
The dealer produces its PMSI paper trail: filed on day twelve, describing the ovens exactly. The court grants the dealer superpriority over those units, and the dealer repossesses and resells them while the bank takes what remains. The group's other equipment supplier, who financed mixers but filed on day thirty-one, recovers pennies in the general queue. The contrast becomes a fixture in the bank workout group's training: Article 9's superpriority is a mechanical prize, won by paperwork on the calendar, and lost by eleven days without any judge finding anyone dishonest.
Watch out
Common mistakes.
- Missing the twenty-day window on equipment; late filing forfeits superpriority and drops the financer into the ordinary first-to-file queue.
- Skipping the inventory notice; without advance notice to earlier filers, the PMSI in inventory never gains its special status.
- Describing collateral loosely; PMSI protection covers only the financed goods, and vague descriptions invite disputes over which units were financed.
Questions
People also ask.
What is a purchase money security interest?
A security interest in goods whose purchase the lender or seller financed, capable of priority over earlier blanket liens when perfected correctly.
How do you perfect one?
For equipment, file within 20 days of the debtor receiving the goods; for inventory, file and notify earlier secured parties before delivery; consumer goods perfect automatically.
Why does the exception exist?
Without PMSI superpriority, a first lender's after-acquired property lien would block all future purchase financing, freezing the borrower's ability to restock.
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