Short answer. The storage company, not you, carries the burden. Article 1978 says permission to use a deposited item is never presumed — its existence must be proved by whoever claims it exists. Without that proof, the arrangement stays a plain deposit, and using your property without it is already a breach.

What the law says

The permission shall not be presumed, and its existence must be proved.

Civil Code, Article 1978 — Permitted Use Converts the Deposit. Read the full provision →

The Default Assumption Favors the Depositor

Ordinarily, a depositary who is permitted to use the deposited thing is no longer acting as a mere custodian of it — the contract effectively shifts into a loan or commodatum instead. But Article 1978 refuses to let that shift happen through mere inference or convenience. Permission "shall not be presumed," which means silence on your part, the depositary's own convenience, or even its own say-so after the fact is not enough on its own. The rule exists precisely because a depositor who is simply storing property, rather than lending it out for someone else's use, rarely thinks to spell out a prohibition that should be obvious without saying.

Who Carries the Burden

Because the law assigns the burden of proof to whoever is asserting that permission was given, a storage company that wants to justify having used your furniture must produce something concrete to back that claim — a signed clause in the contract, a text exchange, or a policy you actually acknowledged — rather than simply asserting the point once a dispute has already started. An internal memo the depositor never saw, or an employee's unverified recollection of a hallway conversation, will typically not carry that burden on its own.

What Happens Without Proof

If the depositary cannot produce that proof, the contract legally remains a straightforward deposit, and using the item without authorization is itself a breach of the basic duty to keep the thing safely on the depositor's behalf. That breach can support a claim for whatever damage, wear, or diminished value resulted from the unauthorized use of the property, and it can also affect who bears the loss if the item is later damaged or destroyed by an event that would otherwise excuse the depositary entirely.

A Practical Note on Documentation

Because verbal understandings are notoriously hard to prove years later, anyone depositing valuable property with a business is better protected by getting the terms — including whether any use of the item is allowed at all — written into the receipt or contract at the very outset, rather than relying on this default rule to sort things out only after a dispute has already arisen. A dated photo or short inventory of the item's condition at drop-off is a simple habit that pays off if a use-without-permission dispute ever reaches a demand letter or a courtroom.

Related provisions

Note. Statute text quoted on this page is reproduced from the official enactment and is linked to the full provision. The explanation around it is general legal information from Vivas & Nobles Law Office, not legal advice. Whether it applies to your situation depends on facts only a lawyer reviewing them can assess.