Definition
A Latin phrase meaning "from, by, or under a will." Ex testamento describes the source or basis of a legal right, claim, or obligation that derives its force from a testamentary instrument — that is, a will. It stands in direct opposition to ab intestato, which describes rights arising from intestate succession, where no valid will governs the disposition of a decedent's estate. The phrase functions as a classificatory marker in succession law, identifying whether property passes, duties arise, or claims are founded on a testamentary act of the decedent.
Common Confusion
Ex testamento is the counterpart of ab intestato, and the two terms define the fundamental binary of succession law: either property passes under a will (ex testamento) or it passes under the law of intestacy (ab intestato). Researchers encountering either phrase in historical legal materials should immediately look to the other, as the contrast between them often carries substantive legal consequences — for heirs, creditors, and executors alike. The phrase should not be confused with ex parte, a superficially similar Latin tag with an entirely different meaning (relating to one-sided proceedings rather than testamentary origin).
Why It Matters in Research
Ex testamento appears primarily in older legal materials — Roman law sources, early English equity proceedings, and nineteenth-century treatises on succession — and is rarely used in modern American or English legal drafting. Researchers working in the Law Mind corpus should expect to encounter it in historical probate records, civil law commentaries, and maxim collections rather than in contemporary case law or statutes.
The phrase carries particular weight in civil law traditions. Burrill's citation to the Institutes (2.9.7) and the Code (6.30.19) signals Roman law lineage, and researchers exploring mixed-jurisdiction succession questions — particularly in Louisiana, Quebec, or comparative law contexts — may find ex testamento appearing in sources that a common law researcher would not anticipate.
One navigational trap in historical sources: the major dictionaries (Black's 1st and 2nd editions, Rapalje & Lawrence, Burrill) all embed ex testamento as a subentry within a block of consecutive Latin maxims beginning with "ex." The surrounding maxims — ex tota materia emergat resolutio, ex turpi causa non oritur actio — are independent phrases with no thematic connection to testamentary law. Researchers scanning historical dictionary pages should take care not to conflate the entries or assume continuity of subject matter across them.
Because ex testamento identifies the testamentary source of a right rather than the substantive content of the right itself, it functions as a procedural and pleading term in historical contexts. In Roman law practice, an actio ex testamento was a specific action to enforce obligations created or recognized by a will. This procedural dimension is largely absent from common law contexts, where the concept is absorbed into the law of probate and estate administration without requiring a distinct Latin label.
Historical Dictionary Support
The four source dictionaries are in complete agreement on the core definition: "from, by, or under a will," with ex testamento understood as the antonym of ab intestato. There is no meaningful divergence among the sources on substance.
Burrill adds the most scholarly depth, citing directly to Roman law sources (Institutes 2.9.7 and Code 6.30.19), grounding the phrase in its classical origins and signaling its relevance to civil law systems. Rapalje & Lawrence similarly flag the ab intestato opposition and note that contracts founded on immoral consideration (ex turpi causa) are void — though that maxim is an independent entry and not substantively connected to ex testamento.
What the historical dictionaries do not address is the procedural Roman law action (actio ex testamento), which would be visible to researchers consulting Justinian's Institutes directly but is absent from the common law dictionary tradition. This gap reflects the dictionaries' orientation toward English and American practice, where the term's significance is definitional and taxonomic rather than procedural.
Jurisdictional Note
Ex testamento is most likely to appear as a live term of art in civil law jurisdictions or in sources engaging Roman law directly. In common law jurisdictions, the concept it describes — rights or claims arising under a will — is handled by the vocabulary of testate succession, probate, and devolution, without resort to the Latin phrase.