Uncertain Agreements under Section 29 of the Indian Contract Act, 1872: The Meaning of Uncertainty, Agreements Capable of Being Made Certain, and the Distinction Between Vagueness and Incompleteness

Section 29 voids agreements the meaning of which is not certain, or capable of being made certain. The qualification is as important as the rule. An agreement does not fail merely because a term is unsettled at the moment of contracting; it fails only where the court has no means of determining what was promised. The courts approach the question with a strong inclination to uphold rather than to destroy, particularly where the parties have acted on the agreement, and the reported cases divide fairly neatly into those where a standard for ascertainment existed and those where the parties had simply not finished negotiating.

Certain, capable of being made certain, or void

1. The Provision

Section 29, Indian Contract Act, 1872

Agreements, the meaning of which is not certain, or capable of being made certain, are void.

Illustrations. (a) A agrees to sell to B a hundred tons of oil. There is nothing whatever to show what kind of oil was intended. The agreement is void for uncertainty.

(b) A agrees to sell to B one hundred tons of oil of a specified description, known as an article of commerce. There is no uncertainty here to make the agreement void.

(c) A, who is a dealer in coconut oil only, agrees to sell to B one hundred tons of oil. The nature of A's trade affords an indication of the meaning of the words, and A has entered into a contract for the sale of one hundred tons of coconut oil.

(e) A agrees to sell to B one thousand maunds of rice at a price to be fixed by C. As the price is capable of being made certain, there is no uncertainty here to make the agreement void.

(f) A agrees to sell to B his white horse for rupees five hundred or rupees one thousand. There is nothing to show which of the two prices was to be given. The agreement is void.

The Illustrations do most of the work of the section and repay close reading. Illustration (a) is void because nothing identifies the subject matter. Illustration (b) is good because a trade description supplies it. Illustration (c) is good because the surrounding circumstances, namely the nature of the seller's business, supply it. Illustration (e) is good because the agreement provides a mechanism. Illustration (f) is void because the agreement offers two alternatives and no means of choosing between them.

2. Sources of Certainty

An agreement is saved wherever a standard exists by which the unsettled term can be ascertained without further agreement between the parties. Five such sources recur.

The agreement itself, which may name a price, a formula, an index, a market rate on a stated date, or a third party who is to fix the term. Illustration (e) is an instance.
Trade usage and the practice of the market, which is preserved by the saving in Section 1 and may supply the meaning of a technical expression.
The nature of the parties' business, as in Illustration (c), where the seller dealt only in one commodity.
A previous course of dealing between the same parties, from which the terms on which they habitually contract may be drawn.
Statutory default rules, such as Section 9 of the Sale of Goods Act, 1930, under which a buyer must pay a reasonable price where the price is not determined by the contract, by a course of dealing or by an agreed mechanism.

3. When an Agreement Fails

📖 Scammell & Nephew Ltd. v. Ouston, [1941] AC 251 (HL)

Facts: The parties agreed on the purchase of a motor van, the order stating that the balance of the purchase price could be had on hire-purchase terms over a period of two years. Nothing further was said about the rate of interest, the amount of the instalments, or which of the many kinds of hire-purchase agreement then in use was intended. The sellers refused to proceed and the buyer sued.

Held: The House of Lords held that there was no enforceable contract. The expression hire-purchase terms was capable of bearing a wide variety of meanings, and there was no standard, usage or previous dealing from which the court could determine which the parties had in mind. The parties had not reached agreement on a matter that was essential, and the court would not make a contract for them by selecting terms itself.

Ratio: Where an essential term is expressed in language capable of many meanings, and nothing supplies a standard for choosing among them, the agreement is void for uncertainty. The court construes contracts; it does not complete them.

3.1 The recurring instances

An agreement to agree. A provision that a term shall be settled by further agreement between the parties leaves the matter to negotiation, not to a mechanism, and is void. A provision that the term shall be settled by a third party or by a formula is good.
Alternatives with no means of choosing, as in Illustration (f).
Terms that are meaningless rather than merely difficult, such as a promise conditional on the subject matter proving satisfactory in a sense the agreement does not define.
Essential terms left blank in a document which the parties nonetheless executed, where nothing outside it supplies the omission.

4. When an Agreement Is Upheld

📖 Hillas & Co. Ltd. v. Arcos Ltd., (1932) 147 LT 503 (HL)

Facts: A contract for the purchase of Russian softwood goods of fair specification during one season contained an option to buy a further quantity in the following season, again expressed by reference to fair specification and without further particulars as to kind, size or shipment dates. The sellers refused to honour the option, contending that it was too uncertain to be enforceable.

Held: The House of Lords held the option binding. The expression had a meaning that could be ascertained from the parties' previous dealings under the first year's contract, from the normal practice of the timber trade, and from the contract read as a whole. Lord Wright observed that the problem is to ascertain by construction, with the aid of the surrounding circumstances, what the parties meant, and that the courts should be reluctant to hold void for uncertainty a provision intended to have legal effect, particularly in a commercial bargain made between parties who understood the trade.

Ratio: The court leans in favour of upholding a commercial agreement that the parties intended to be binding, and will resort to previous dealings, trade practice and the document as a whole to supply a meaning before holding a term void for uncertainty.

⚠ Vagueness and incompleteness are different objections

An agreement may fail in two distinct ways, and the pleadings should be clear which is alleged. It is vague where the parties have used language that has no ascertainable meaning, as in Scammell v. Ouston; the court cannot tell what was agreed. It is incomplete where an essential term was never addressed at all, so that there is nothing to construe; the parties had not finished negotiating and no contract came into existence. Vagueness is answered by looking for a standard of ascertainment. Incompleteness is answered by asking whether the parties intended to be bound notwithstanding the gap, and whether a default rule such as Section 9 of the Sale of Goods Act, 1930 fills it.

5. Certainty and Related Provisions

Situation	Governing provision	Result
The agreement supplies a mechanism for fixing the term	Section 29, Illustration (e)	Valid. The term is capable of being made certain
Price not fixed in a contract for the sale of goods	Section 9, Sale of Goods Act, 1930	Valid. The buyer must pay a reasonable price, which is a question of fact
The parties are at cross purposes about the identity or measure of the subject matter	Section 20	Void for bilateral mistake, not for uncertainty; the difference matters for restitution under Section 65
The parties intend not to be bound until a formal document is executed	General principles of offer and acceptance	No contract yet; the objection is absence of intention to be bound rather than uncertainty
An uncertain term that is severable and not essential	Section 29, on the authorities	The term may be struck out and the rest of the agreement enforced
A term to be settled by further agreement between the parties	Section 29	Void, being an agreement to agree

5.1 Uncertainty distinguished from mistake

Where the parties used words that have no ascertainable meaning, the agreement is void for uncertainty under Section 29. Where the words were clear enough but each party understood them to refer to a different thing, the agreement is void for bilateral mistake under Section 20. The classic illustration of the second is the two ships named Peerless in Raffles v. Wichelhaus, (1864) 2 H & C 906, where the description was perfectly definite and the difficulty was that it fitted two subject matters. The distinction is not merely taxonomic: Section 65 requires restoration of any advantage received under an agreement discovered to be void, and the route to voidness must be identified before relief is framed.

6. The Approach of the Courts

The lean is towards upholding. Where the parties plainly intended to create legal relations and have acted on the agreement, the court will strive to find a meaning rather than declare the bargain a nullity.
Performance is powerful evidence of certainty. Where the parties have performed for a period without difficulty, their conduct usually shows that the term had an ascertainable meaning.
The commercial setting matters. Expressions that would be meaningless to an outsider often have a settled meaning in a particular trade, and evidence of that usage is admissible.
The court construes, it does not complete. Where the gap can be filled only by choosing among several possibilities the parties never considered, the agreement fails, because supplying the term would be making a contract for them.
Severance is available for an inessential term. An uncertain provision that can be struck out without altering the substance of the bargain leaves the rest standing.

7. The Position Stated Shortly

Section 29 voids agreements whose meaning is not certain or capable of being made certain.
The Illustrations show the sources of certainty: a trade description, the nature of the seller's business, and a mechanism such as valuation by a named third party.
Certainty may also be supplied by trade usage, a previous course of dealing, and statutory default rules such as Section 9 of the Sale of Goods Act, 1930.
Scammell v. Ouston: an expression capable of many meanings, with no standard for choosing among them, makes the agreement void.
An agreement to agree is void; an agreement to have a term fixed by a third party or a formula is not.
Hillas v. Arcos: the courts lean towards upholding a commercial bargain the parties intended to be binding, using previous dealings and trade practice.
Vagueness and incompleteness are different objections and are answered differently.
Uncertainty under Section 29 must be distinguished from bilateral mistake under Section 20, where the words are definite but fit two subject matters.
An inessential uncertain term may be severed, leaving the remainder of the agreement enforceable.

8. Related Topics and Provisions

Topic or provision	Connection
Void Agreements under Sections 24 to 30	Section 29 among the classes declared void
Mistake under Sections 20 to 22	Bilateral mistake, distinguished from uncertainty
Offer or Proposal under Section 2(a)	Certainty as an essential of a valid offer
Acceptance vs Counter Offer	Agreements subject to a formal document being executed
Section 29, Indian Contract Act	The provision and its Illustrations
Section 1, Indian Contract Act	The saving of usage and custom of trade
Section 20, Indian Contract Act	Bilateral mistake of fact essential to the agreement
Section 65, Indian Contract Act	Restoration where an agreement is discovered to be void
Section 9, Sale of Goods Act, 1930	Reasonable price where the price is not determined