The Mandate in French Commercial Lease Transactions
A mandat under French law is the contract by which one person (the mandant, or principal) gives another person (the mandataire, or agent) the power to act on their behalf and in their name (C. civ. Art. 1984). Applied to French commercial lease transactions, the mandate is the instrument by which a landlord or tenant authorises a third party — a property manager, a lawyer, a broker, a family member, a director's delegate — to conclude or renew the lease on their behalf.
The mandate is an indispensable tool in practice. Landlords and tenants are frequently absent, geographically remote, or simply unable to attend to the transaction personally. The mandate allows the lease to be concluded and executed as effectively as if the principal had been physically present. A lease can even be concluded when neither party is present, both acting through their respective agents.
The central legal questions the mandate raises in commercial lease transactions are: does the agent have sufficient authority for the specific act they are performing? If not, does apparent authority protect the third party? And if the agent acts entirely without authority, what consequences follow for each party?
The Express Mandate Requirement for Granting a French Commercial Lease
Granting a Lease Is an Act of Disposition
The fundamental rule of French mandate law is that a general mandate authorises only acts of administration; an act of disposition requires an express mandate (C. civ. Art. 1988). The classification of a particular act as administration or disposition therefore determines whether a specific mandate is required or whether a general authority to manage will suffice.
Granting a French commercial lease in the capacity of landlord is an act of disposition (Cass. 1e civ. 17-5-1993 n° 91-20.112). The statutory protections conferred on the tenant — above all the right to renewal and the right to an eviction indemnity if renewal is refused — make the grant of a commercial lease a significant commitment of the landlord's property rights. Accordingly, an agent must hold an express mandate to grant a commercial lease on behalf of a landlord. A general property management mandate, however comprehensive it may appear, does not authorise this act unless it expressly extends to it.
Taking a Lease Is an Act of Administration
The position for tenants is different. Taking a commercial lease as a tenant is a less weighty act than granting one as landlord, and French law treats it as an act of administration. An agent acting under a general mandate may therefore take a commercial lease on behalf of their principal. That said, given the nine-year commitment and the financial consequences, the safest approach in practice is always to obtain an express mandate whether the agent is acting as landlord or tenant, to eliminate any possibility of challenge.
"Express" in the mandate context does not mean the mandate must be in writing. A verbal mandate is legally valid even for the grant of a commercial lease (C. civ. Art. 1985 al. 1). "Express" means that the mandate must specifically identify the operation authorised — the grant of a lease of specific premises. A mandate that merely authorises someone to "administer" or "manage" a building is too imprecise. Conversely, a mandate that expressly authorises the grant of a commercial lease, leaving the specific rent level to the agent's discretion, remains a valid express mandate even though a specific figure is not prescribed: the operation itself is identified, and the agent is authorised to determine the commercial terms.
Verification by the Third Party: The Article 1158 Mechanism
A third party who doubts the extent of an agent's authority has a specific right under Article 1158 of the Civil Code: they may write to the principal directly to ask for confirmation that the agent is authorised to conclude the specific act in question. The request must fix a reasonable response deadline and state that failure to respond within that period will be treated as confirmation that the agent is duly authorised. This mechanism provides the counterparty with a formal protection against later challenge from the principal who claims the agent lacked authority.
The mechanism works best when used proactively. A prospective tenant who receives an offer of commercial lease from a person presented as the landlord's agent — particularly where the agent's authority is not documented in writing — should seriously consider invoking this right before accepting. A written confirmation from the principal that the agent is authorised eliminates the risk of the principal later claiming unenforceability on grounds of lack of authority.
Apparent Authority (Mandat Apparent): When the Principal Is Bound Without Actual Authority
The most practically significant aspect of the French law of mandate for commercial lease transactions is the doctrine of mandat apparent (apparent authority). Under Article 1156 of the Civil Code, a principal may be bound by acts of a person who had no actual mandate, where third parties legitimately believed that person to have authority. This protects the counterparty who transacted in good faith on the basis of appearances created — at least in part — by the principal's own conduct.
The Requirements for Apparent Authority
Three conditions must be met for the doctrine to apply. First, the third party must have had a croyance légitime — a legitimate belief — that the person they were dealing with had authority to conclude the act. Second, that belief must have been objectively reasonable in the circumstances: the mere assertion by the purported agent that they have authority is never enough on its own, since that is a declaration of the purported agent alone. Third, the principal must not have been entirely unconnected to the creation of the appearance: the appearance must derive, at least in part, from the principal's own conduct, declarations, or omissions (Cass. com. 29-6-2022).
The legitimate belief is assessed at the moment of the act, not in hindsight (Cass. 3e civ. 20-4-1988). Subsequent events — for example, a principal who later denies the agent's authority — cannot retroactively undermine a belief that was legitimate when it was formed.
What Creates a Legitimate Belief
Courts apply a multi-factor test drawn from the surrounding circumstances of each transaction. The following factors consistently weigh in favour of legitimate belief:
- The purported agent belongs to a profession whose normal activities include concluding commercial leases (a property management firm, a real estate agent, a notary's clerk) — such professional character creates a strong presumption of authority.
- The principal has previously allowed the same person to conclude leases, collect rents, grant quittances, and consent to renewals over an extended period without ever challenging their authority.
- Multiple parties, including co-owners or co-signatories, participated in the act, creating a reinforcing appearance of authorisation.
- The principal had knowledge of ongoing negotiations and did not intervene to signal the absence of authority.
What Does Not Create a Legitimate Belief
Courts are equally clear about situations where apparent authority cannot be invoked. A counterparty who could easily have verified the agent's actual authority but chose not to cannot generally rely on apparent authority.
When apparent authority is established, the principal is bound by the lease as though they had granted actual authority. The apparent agent, having acted without actual mandate, is not personally bound by the lease (Cass. com. 21-3-1995). However, any damage caused to the third party by the apparent agent's conduct falls on the principal — including liability for misappropriated funds paid to the apparent agent in connection with the lease (CA Paris 5-3-2009). The principal's sole remedy is against the person who created the appearance of authority, which may be difficult or worthless if that person is impecunious.
Acting Without or Beyond Authority: Consequences for Each Party
Where an agent acts entirely without a mandate, or exceeds the scope of a mandate they hold, the consequences depend on whether the third party is protected by apparent authority and on the timing of the lease.
For leases concluded since 1 October 2016, the act of an agent without authority is inopposable to the principal (C. civ. Art. 1156 al. 1): the principal cannot be required to perform it. For leases before that date, the same result was reached through the doctrine of relative nullity: only the principal could invoke the nullity, not the third party (Cass. 1e civ. 2-11-2005). In both cases, the principal may choose to ratify the act, in which case the lease becomes fully effective as of its original date (C. civ. Art. 1156 al. 3). Ratification requires no particular form and may be express or tacit — it may result from any conduct that unambiguously manifests the principal's intention to accept the act.
The Unauthorised Agent's Liability
Where an agent has no authority and the third party is not protected by apparent authority, the lease does not bind the principal. The third party's remedy, where they transacted in good faith, is an action against the unauthorised agent for damages for breach of the implied warranty of authority. The agent who concluded a lease "on behalf of" a person who gave no mandate has induced the third party to believe they were dealing with an authorised representative; their personal liability for the resulting harm is well established in French law.
Mandate Diversion: The Abuse of Authority
A mandate that is formally valid may still be turned against the principal if the agent uses it for purposes contrary to the principal's interests. Where the agent diverts (détourne) their mandate — for example, concluding a lease at an undervalue in exchange for a concealed payment from the tenant — the principal may seek nullity of the lease if the third party knew of the diversion or could not have been unaware of it (C. civ. Art. 1157). The standard is bad faith: collusion between agent and third party is not required. This has direct relevance in commercial lease contexts where agents receive undisclosed payments from the other side of a transaction.
The Agent's Duties and Liability Towards the Principal
An agent negotiating a French commercial lease on behalf of their principal owes a range of duties. Understanding these is important for principals who have suffered loss through poor agency performance, and for agents seeking to limit their exposure.
The Principal's Obligations to the Agent
The mandate is a bilateral contract. The principal also has obligations to the agent, which arise independently of whether the transaction was completed successfully.
The principal must reimburse the agent for all advances and expenses incurred in execution of the mandate, even if the transaction did not succeed, provided the agent was not at fault (C. civ. Art. 1999). This reimbursement obligation cannot be escaped by pointing to an unsuccessful outcome: the agent who actively searched for a tenant without finding one is entitled to reimbursement of their costs if they acted without fault. The principal must also indemnify the agent for losses suffered in the course of the mandate (C. civ. Art. 2000), unless those losses were caused by the agent's own negligence.
Where a remuneration was agreed, it is due on performance of the mission — not necessarily on completion of the transaction. An agent who successfully found a tenant for a commercial lease and negotiated terms, but whose principal subsequently withdrew from the transaction, may still be entitled to their fee if the mandate defined the mission as finding and introducing a prospective tenant rather than as executing the final lease.
How the Mandate Ends
A mandate may end in several ways, each with distinct consequences for leases already concluded or in course of negotiation.
The principal may revoke the mandate at any time (C. civ. Art. 2004), even if the parties agreed a fixed term or declared the mandate "irrevocable". An irrevocability clause does not deprive the principal of the power to revoke; it merely gives the agent a right to compensation if the revocation was abusive or premature. Revocation takes effect from the moment the agent is informed of it. Critically, revocation notified to the agent alone is unenforceable against third parties who dealt with the agent in ignorance of the revocation: the principal remains bound by acts concluded by a revoked agent with third parties who had no knowledge of the revocation (C. civ. Art. 2005).
The mandate also ends by the death of either party (C. civ. Art. 2003). Where the principal dies, the agent must complete urgent acts already commenced before ceasing. Engagements taken by the agent after the principal's death, but in ignorance of it, are valid and enforceable against the estate by third parties who dealt in good faith. The incapacity of either party (placement under tutelle) also terminates the mandate. The liquidation judiciaire of the agent, however, does not automatically terminate a mandate not yet executed: the insolvency regime preserves ongoing contracts (Cass. com. 28-6-2017 n° 15-17.394).
Whether you are a principal seeking to confirm authority, a counterparty questioning whether an agent was duly mandated, or an agent navigating the limits of your instructions, our guides and legal contacts are here to help you assess and structure the arrangement correctly.
Book a ConsultationThis article is for general information and educational purposes only. It does not constitute legal advice and does not create a lawyer-client relationship. The legal framework described reflects French law as at 2025. Always seek qualified French legal advice before concluding, assigning, or terminating a French commercial lease through an agent.
Key Legal References
Definition of mandate (mandat): a contract by which one person (the mandant, or principal) gives another person (the mandataire, or agent) the power to act on their behalf and in their name
Form and proof of mandate: a verbal mandate is legally valid even for the grant of a commercial lease. The mandate need not be in writing unless the law or the parties specifically require it
General vs express mandate: a general mandate authorises only acts of administration; an act of disposition requires an express mandate specifically identifying the operation authorised. A mandate authorising 'administration' or 'management' of a building is too imprecise to authorise the grant of a commercial lease
Granting a French commercial lease as landlord is an act of disposition: the statutory protections conferred on the tenant (right to renewal, right to eviction indemnity) make the grant a significant commitment of the landlord's property rights. An agent must hold an express mandate to grant a commercial lease on behalf of a landlord
Third party verification right: a third party who doubts the extent of an agent's authority may write to the principal to request confirmation, fixing a reasonable response deadline and stating that silence within that period will be treated as confirmation that the agent is duly authorised
Apparent authority (mandat apparent): the principal may be bound by acts of a person who had no actual mandate where third parties legitimately believed that person to have authority. Three conditions: (1) croyance légitime — legitimate belief; (2) objectively reasonable in the circumstances; (3) appearance derives at least in part from the principal's own conduct, declarations, or omissions. For post-2016 leases, act without authority is inopposable to the principal; principal may ratify expressly or tacitly
Mandate diversion (abus de pouvoir): where the agent uses a formally valid mandate for purposes contrary to the principal's interests, the principal may seek nullity of the resulting act if the third party knew of the diversion or could not have been unaware of it. Standard is bad faith; collusion is not required. Applies where agents receive undisclosed payments from the other side of a transaction
Duty to execute the mandate strictly: the agent must perform the mission entrusted and may do nothing beyond what the mandate authorises. Scope of authority is construed strictly. Total non-performance: agent's liability presumed. Defective performance: principal must prove fault
Loyalty duty of the agent: the agent must disclose to the principal any information that may affect the principal's decision, including information that might lead the principal to reconsider the terms or the transaction
Duty to account: the agent must render account to the principal for all sums received in execution of the mandate, including sums received from third parties. Misappropriation of client funds: abuse of trust (abus de confiance)
Liability standard: paid agent held to strict standard of fault; gratuitous agent subject to more indulgent assessment of fault only (not quantum of damages if fault is found)
Principal's duty to reimburse agent for advances and expenses incurred in execution of the mandate, even if the transaction did not succeed, provided the agent was not at fault
Principal's duty to indemnify agent for losses suffered in the course of the mandate, unless caused by the agent's own negligence
Revocation: the principal may revoke the mandate at any time even if a fixed term or irrevocability was declared. Irrevocability clause = damages for abusive/premature revocation only, not prevention of revocation. Revocation unenforceable against third parties who dealt with the agent in ignorance of it — principal remains bound by post-revocation acts with uninformed third parties
Termination by death or incapacity: mandate ends on death of either party or placement under tutelle; agent must complete urgent acts commenced before ceasing; post-death acts by agent in ignorance of death are valid against the estate for uninformed third parties
Liquidation judiciaire of the agent does not automatically terminate a mandate not yet executed: the insolvency regime preserves ongoing contracts
