Definition
A condition collateral is a condition attached to a legal obligation — most commonly in a deed, contract, or conveyance — where the act required to be performed is collateral to the main subject matter of the transaction. That is, the condition does not relate directly to the land, property, or primary obligation being transferred or created, but instead requires the performance of some separate, independent act as a precondition or subsequent condition of the grant or agreement.
For example, a conveyance of land conditioned upon the grantee building a church in another county, or paying a sum of money to a third party, would impose a condition collateral: the required act stands apart from the property itself. The condition's character as "collateral" distinguishes it from conditions that are intrinsic to the estate or obligation being created.
Common Confusion
Condition collateral should not be confused with condition precedent or condition subsequent, which classify when a condition must be fulfilled relative to the vesting of an interest (before or after), rather than describing the nature of the act itself. A condition collateral describes what the required act is — something separate from the subject matter of the grant — and can itself be either precedent or subsequent in timing. The two classification systems operate on different axes and can overlap: a condition collateral may also be a condition precedent, if the collateral act must be performed before the interest vests.
Researchers should also take care not to conflate this term with the collateral source rule in tort law or with collateral consequences in criminal law, which are entirely distinct doctrines sharing only the modifier "collateral."
Why It Matters in Research
This term appears almost exclusively in older property law and conveyancing literature, particularly in the context of the law of conditions in deeds. Researchers working with historical real property sources — especially materials predating the twentieth century — will encounter it in discussions of how conditions were classified, how their breach was measured, and what remedies followed.
The classification of a condition as collateral (versus, for instance, a condition precedent or subsequent, or a condition going to the essence of the grant) had practical consequences in equity and at common law: courts assessed whether a collateral condition could be separated from the grant, whether its breach triggered forfeiture, and whether specific performance or damages were the appropriate remedy.
The primary source cited by both Black's and Burrill's — Sheppard's Touchstone of Common Assurances (1648) — is the foundational text here. Researchers relying on American secondary sources should be aware that this classification scheme derives almost entirely from early English conveyancing doctrine and may not map cleanly onto modern property codes, which rarely use this precise terminology.
Modern legal usage has largely absorbed this concept into the broader framework of conditions in contracts and real property law without preserving the "collateral" label as a distinct term of art. Researchers searching nineteenth-century American treatises, English chancery reports, or deed construction cases will find the term actively used; modern case law and statutes will rarely use it by name.
Historical Dictionary Support
Black's Law Dictionary and Burrill's Law Dictionary are in complete agreement, offering identical definitions and citing the same source: Sheppard's Touchstone of Common Assurances at page 118. The convergence is unsurprising — both dictionaries drew heavily on English conveyancing authority for property law terminology, and Sheppard's Touchstone was the dominant treatise on deed construction for two centuries.
Neither dictionary elaborates on the practical legal consequences of breach, the distinction from other condition types, or the equitable treatment of collateral conditions. This is a gap researchers should note: the bare definition tells you what the condition is, but not how courts handled it. For that, Sheppard's Touchstone itself, along with Preston's Abstracts of Title and Platt on Covenants, are the more instructive primary sources.
Both entries treat the term as self-evidently settled doctrine — appropriate for their era, but a caution to modern researchers that the concept is not actively litigated or defined in contemporary authority.
Encyclopedia Cross-Reference
For related but distinct uses of "collateral" in other areas of law, see: Defenses to Negligence — Collateral Source Rule (The Law Mind Torts & Personal Injury Encyclopedia); Collateral Consequences of Criminal Conviction (The Law Mind Criminal Law Encyclopedia).