Definition
An heir conventional is, in civil law, a person who succeeds to a decedent's estate not by operation of law or by blood relationship alone, but by virtue of a contract or settlement that entitles them to that succession. The right to inherit arises from an agreement — typically made during the decedent's lifetime — rather than from the default rules of intestate succession.
The term belongs to civil law systems (Roman law, French law, Louisiana law, and their descendants) rather than to the common law tradition. In those systems, succession law distinguishes sharply between heirs whose claim derives from law, heirs whose claim derives from testament, and heirs whose claim derives from a prior contractual arrangement. The heir conventional falls into the third category.
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Common Confusion
HEIR CONVENTIONAL vs. HEIR BY TESTAMENT: These are not the same. A testamentary heir takes under a will executed unilaterally by the decedent and revocable until death. A conventional heir takes under a bilateral agreement — a contract — which may not be unilaterally revoked. The contractual basis is the defining feature.
HEIR CONVENTIONAL vs. FORCED HEIR: A forced heir cannot be disinherited regardless of the decedent's wishes — the right flows from law, not agreement. An heir conventional, by contrast, derives their right from contract. The two concepts operate on entirely different legal foundations, though Black's Law Dictionary places the entry for forced heir immediately adjacent to heir conventional, which can create confusion for researchers scanning that passage.
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Why It Matters in Research
This term is primarily a civil law artifact. Researchers working in common law jurisdictions will rarely encounter it in modern case law or statutes, but will encounter it frequently when reading historical civilian sources, treatises on Louisiana succession law, or comparative law materials.
Jurisdictional trap: Louisiana is the primary American jurisdiction where this concept retains operational significance, owing to its civilian heritage. A researcher applying common law inheritance frameworks to Louisiana succession problems risks fundamental error. Louisiana's Civil Code provisions on succession and the rules governing certain matrimonial agreements and donations mortis causa can create what functions as conventional heirship in ways that have no common law analogue.
Historical source trap: Older civilian dictionaries and treatises use the full taxonomy of heir types — heir apparent, heir presumptive, heir at law, heir conventional, forced heir, irregular heir — as a structured system. When Black's Law Dictionary reproduces these entries, it is largely reporting civilian doctrine, not describing rules operative in most American courts. Researchers should not read the Black's entry as a statement of prevailing American common law.
Corpus connection: When this term appears in primary source documents in the Law Mind corpus — particularly in Louisiana materials, notarial records, or civil law treatises — it signals that the document is operating within a civilian succession framework. That framing should recalibrate how the researcher reads adjacent terms like donation, legitime, forced portion, and universal successor.
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Historical Dictionary Support
Black's Law Dictionary provides a spare entry: "One who takes a succession by virtue of a contract or settlement entitling him thereto." This definition is accurate as far as it goes but offers no context about the civil law system in which the concept lives, no explanation of what kinds of contracts create this status, and no indication of how the concept differs jurisdictionally.
The placement of this entry — immediately before the entry for forced heir — reflects the civilian taxonomy Black's was drawing on, but the compressed format means the structural relationship between categories of heirs is not explained. Researchers relying solely on Black's will know what the term means in isolation but not why the distinction matters or how it fits within civil law succession doctrine as a whole.
Historical civilian sources, including Pothier and Domat, provide much richer accounts of the contractual basis for succession and the enforceability of such arrangements. Those sources distinguish carefully between contracts that create a present right (irrevocable) and testamentary dispositions that remain ambulatory. Black's does not capture this distinction.
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Jurisdictional Note
Outside Louisiana, this term has virtually no operational significance in American law. Common law jurisdictions generally prohibit contracts to make a will or to leave property to a specific person, treating such agreements as against public policy or unenforceable as a matter of the Statute of Frauds or its successors. Louisiana's civilian framework is the exception, and researchers should treat the concept as Louisiana-specific unless working in comparative or historical contexts.
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Encyclopedia Cross-Reference
The Law Mind Trusts, Estates & Probate Encyclopedia — Escheat: When Property Passes to the State for Lack of Heirs (estates_9): relevant background on how heir status — including the failure to identify qualifying heirs — affects the ultimate disposition of an estate.
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