Interlineation

The process of writing between the lines of an instrument; that which is written between the lines of a document.

An interlineation frequently appears in a contract that has been typed and signed. If the parties agree that a sentence is to be inserted between the lines to clarify a particular provision, the new sentence is known as an interlineation. The new line should be initialed and dated to indicate that both parties are aware of and agree to its insertion. An interlineation results in the alteration of an instrument.

Cross-references

Alteration of Instruments.

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interlineation n. the act of writing between the lines of a document, usually to add something that was omitted or thought of later. The issue (debated question) is whether both parties to a document (a contract, for example) had agreed upon the addition, or whether the new words were part of the document (like a will) when it was signed. Good practice is either to have all parties initial the change at the point of the writing or have the document re-typed and then signed.

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INTERLINEATION, contracts, evidence. Writing between two lines.
     2. Interlineations are made either before or after the execution of an instrument. Those made before should be noted previously to its execution; those made after are made either by the party in whose favor they are, or by strangers.
     3. When made by the party himself, whether the interlineation be material or immaterial, they render the deed void; 1 Gall. Rep. 71; unless made with the consent of the opposite party. Vide 11 Co. 27 a: 9 Mass. Rep. 307; 15 Johns. R. 293; 1 Dall. R. 57; 1 Halst. R. 215; but see 1 Pet. C. C. R. 364; 5 Har. & John; 41; 2 L. R. 290; 2 Ch. R. 410; 4 Bing. R. 123; Fitzg. 207, 223; Cov. on Conv. Ev. 22; 2 Barr. 191.
     4. When the interlineation is made by a stranger, if it be immaterial, it will not vitiate the instrument, but if it be material, it will in general avoid it. Vide Cruise, Dig. tit. 32, c. 26, s. 8; Com. Dig. Fait, F 1.
     5. The ancient rule, which is still said to be in force, is, that an alteration shall be presumed to have been made before the execution of the instrument. Vin. Ab. Evidence, Q, a 2; Id. Faits, U; 1 Swift's Syst. 310; 6 Wheat. R. 481; 1 Halst. 215. But other cases hold the presumption to be that a material interlineation was made after the execution of an instrument, unless the contrary be proved. 1 Dall. 67. This doctrine corresponds nearly with the rules of the canon law on this subject. The canonists have examined it with care. Vide 18 Pick. R. 172; Toull. Dr. Civ. Fr. liv. 3, t. 3, c. 4, n. 115, and article Erasure.