Definition
Ex locato is a Latin phrase meaning "from or out of a letting" or "from or out of a lease." In civil law, it describes actions or rights of action arising from the contract of locatum — the Roman law contract by which one party (the locator) delivered a thing, service, or work to another (the conductor) in exchange for hire or rent. An action ex locato was the remedy available to the locator — the party who let out the thing or service — to enforce the terms of that contract or recover for its breach.
The phrase functions as a directional marker: it identifies which party's claim is at issue and under what legal theory. The corresponding action available to the conductor (the party who received the thing or service) was ex conducto.
Common Confusion
Ex locato is paired with ex conducto, the corresponding action available to the conductor — the party who hired or received the thing or service. The two terms are mirror images: ex locato belongs to the lessor or letter; ex conducto belongs to the lessee or hirer. Conflating them reverses the parties and the direction of the claim. Researchers should also take care not to confuse locatum-derived terminology with the modern lease or employment contract, which developed along different doctrinal lines in common law jurisdictions.
Why It Matters in Research
Ex locato is a term of civil law origin that was adopted into early English legal practice and appears in medieval and early modern sources. Researchers working in pre-modern English legal records — particularly those involving disputes over hire of goods, services, or labor — may encounter this phrase in contexts that do not map cleanly onto modern contract or property categories.
The critical navigational point: ex locato belongs to the locatum family of civil law contracts, which covered a wide and heterogeneous range of arrangements — hire of a thing (locatio rei), hire of services (locatio operarum), and hire of work or result (locatio operis faciendi). A researcher who encounters ex locato in a historical source must determine which subtype of locatum underlies the action, because the practical subject matter may be anything from lease of land to carriage of goods to employment of a craftsman.
In early English legal sources, particularly Bracton, civil law terminology was absorbed into the common law framework imperfectly. The phrase ex locato may appear in contexts that later common law would classify under assumpsit, bailment, or landlord-tenant rather than anything resembling a unified "locatum" action. Tracing this evolution requires careful attention to which historical stratum of legal authority is being consulted.
The term has no meaningful presence in modern Anglo-American legal practice. It surfaces today almost exclusively in legal history scholarship, Roman law study, and the glossarial apparatus of historical legal dictionaries. Researchers should not expect to find it in modern case reporters or statutory indexes.
Historical Dictionary Support
Black's Law Dictionary (both editions) and Burrill's Law Dictionary are in close agreement on this entry, and all three sources draw from the same pair of authorities: Justinian's Institutes (Book 4, Title 6) and Bracton's De Legibus et Consuetudinibus Angliae (fol. 102), with secondary confirmation from Reeves' History of English Law. This convergence reflects the term's straightforward civil law genealogy rather than any contested meaning.
Black's adds the gloss "lease or letting" where Burrill stays closer to "letting" alone — a minor stylistic difference without substantive consequence. None of the historical dictionary sources elaborate on the distinction between the three subtypes of locatum, which is a meaningful gap for researchers who need to understand what kind of dispute an ex locato action would actually have involved. For that analysis, the Institutes themselves and secondary Roman law scholarship are more useful than the dictionary entries.
All three sources flag the English adoption via Bracton, correctly noting that ex locato entered English legal practice at an early period. None traces what happened to this action as English common law diverged from civilian procedure — a silence that accurately reflects the term's limited footprint in post-medieval English jurisprudence.