Definition
In old English law, a concessio was a grant — specifically, one of the recognized common assurances, or formal modes of conveyance, used to transfer property rights. The term is Latin for "grant" and appears in historical English legal sources as both a standalone term and as the root of two enduring maxims of grant construction.
Concessio was understood to be the proper form for conveying incorporeal hereditaments — rights and interests that have no physical existence, such as easements, rents, advowsons, and similar property — which could not pass by livery of seisin and therefore required a deed. In this respect it was distinguished from feoffment, which conveyed corporeal interests in land through physical delivery.
Two Latin maxims are closely attached to the term and carry independent legal weight:
1. Concessio versus concedentem latam interpretationem habere debet. A grant ought to be broadly (liberally) interpreted against the grantor. This is the civil-law ancestor of the modern rule that ambiguities in a conveyance are construed against the party who drafted or made the grant.
2. Concessio per regem fieri debet de certitudine. A grant by the king ought to be made from certainty. This maxim reflects the stricter rule governing royal grants: because the Crown's grants are acts of sovereign prerogative, they must be specific and certain in their terms, and ambiguity is not resolved against the Crown in the same liberal manner applied to private grantors.
Common Language
Modern common usage (Wiktionary): A rhetorical device in which a speaker concedes or admits a point while minimizing or pardoning its significance.
Historical common usage (Webster's 1913): Not separately defined; the English word "concession" derives from the same Latin root and carried the sense of yielding or granting something to another.
Editorial note: The rhetorical sense of concessio — admitting a point to soften an argument — has no connection to its legal meaning. In legal sources, concessio is purely a term of conveyancing and property law. A researcher encountering the word in a historical legal text should not carry over the rhetorical sense.
Common Confusion
Concessio is sometimes loosely equated with "grant" as though the two are interchangeable in all contexts. They are functionally synonymous for many purposes, but concessio in historical sources specifically signals the formal conveyancing act, and often appears precisely because the drafter wanted to emphasize that the subject matter was an incorporeal right requiring that form. Additionally, the two attached maxims are sometimes cited as general canons of construction without their historical grounding in concessio being recognized; researchers should understand that these maxims arose specifically in the context of royal and private grants of property, not agreements or contracts generally.
Why It Matters in Research
Researchers working in historical English property law, land records, or early American conveyancing will encounter concessio most often in one of three forms: as a term of art in older treatises on common assurances (alongside feoffment, bargain and sale, and lease and release); as the heading or operative word in historical deed forms; or embedded in the two Latin maxims, which appear in case law and treatises well beyond their historical origins.
The maxim contra concedentem (construing grants against the grantor) has a long afterlife in American and English case law on easements, deed construction, and patent grants, and its root in concessio is rarely flagged in modern opinions. A researcher tracing the intellectual lineage of the contra proferentem rule as applied to deeds and property grants will find concessio an essential waypoint.
The royal grant maxim (certitudine) is particularly important for researchers working on Crown grants, early colonial land patents, and public land dispositions. Courts applying this rule reached results directly opposite to the liberal-construction rule applied to private grantors — a divergence that has caused confusion when both maxims appear in the same secondary source without clear differentiation.
Because concessio as a distinct conveyancing form largely disappeared from active use after the Statute of Frauds and the modernization of English land law, it rarely appears in sources after the eighteenth century except as historical reference. Do not expect to find it in American statutory codes or modern practice materials.
Historical Dictionary Support
All three source dictionaries — Black's (1st and 2nd editions) and Burrill's — agree on the core definition: concessio is a grant and one of the old common assurances, specifically suited to incorporeal hereditaments. Burrill adds the most doctrinal texture by citing Coke on Littleton and Blackstone's Commentaries, grounding the term in its proper conveyancing context and noting the requirement of a deed. Both Black's editions reproduce the two maxims and cite 9 Coke 46 for the royal grant rule and Jenk. Cent. 279 (Jenkins' Centuries of Reports) for the liberal-construction rule.
What the historical dictionaries do not address is the divergence in treatment between the two maxims, or the downstream influence of the liberal-construction maxim on modern deed interpretation. They present concessio as a historical artifact rather than a living source of interpretive principle — which understates its continued relevance to grant-construction doctrine.
Jurisdictional Note
Concessio as a formal conveyancing term is a creature of English common law and has no direct equivalent in civil-law jurisdictions. In American law, the term appears primarily in historical materials and in cases tracing the roots of contra-grantor construction rules; it is not a term of art in any current American jurisdiction's property statutes.