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Part I Fundamentals, 2 Principles

From: Contract Law in Practice

Neil Andrews

From: Oxford Legal Research Library (http://olrl.ouplaw.com). (c) Oxford University Press, 2023. All Rights Reserved. Subscriber: null; date: 06 June 2023

Agency by estoppel — Breach of contract — Interpretation of contract — Contract clauses and damages

(p. 21) Principles

Freedom of Contract

Six Main Principles.

2.01  The six major principles of English contract law are: freedom of contract; the objective principle; the contractual bond principle (pacta sunt servanda); estoppel; the (latent) principle of good faith; and the compensation principle (on each of these principles, see the ensuing text in this chapter).

Freedom of Contract.

2.02  This is the pre-eminent principle:1 parties can form agreements when and on which terms they wish, subject only to overriding restrictions based on public policy. More precisely, freedom of contract comprises a set of five powers exercisable by individuals and legal entities, notably:

  1. (1)  parties have a general freedom to enter into legally binding transactions; conversely, parties are free to ‘walk away’ from a proposed deal, if they have not already committed themselves to a binding agreement;

  2. (2)  but even when agreement is reached, the parties can stipulate that it will not be legally binding;

  3. (3)  the parties have the power to formulate individual terms within such a transaction (or to acquiesce in default terms, whether these are implied by statute or at Common Law);

  4. (4)  exercise of the powers mentioned at (1) to (3) presupposes that each party’s purported consent is a free decision and not the product of, for example, duress or another vitiating factor;

  5. (5)  courts must respect the parties’ agreement and not rewrite it without the parties’ clear consent.

2.03  Another facet of freedom of contract is that burdens cannot be thrust on third parties by contracting parties. That aspect is noted, together with various qualifications at [9.98]: ‘Privity of Contract and “Burdens” ’.

(p. 22) 2.04  The classic statement (made in response to an unsuccessful plea that a contract was contrary to public policy) is by Sir George Jessel in Printing & Numerical Registering Co v Sampson (1875):2

if there is one thing which more than another public policy requires it is that men of full age and competent understanding shall have the utmost liberty of contracting, and that their contracts when entered into freely and voluntarily shall be held sacred and shall be enforced by Courts of justice. Therefore, you have this paramount public policy to consider—that you are not lightly to interfere with this freedom of contract.

Judicial Affirmations of the Principle.

2.05  There have been other important judicial references to this principle, including the following passages:

  1. (1)  Blackburn J, in Bettini v Gye (1876):3

Parties may think some matter, apparently of very little importance, essential; and if they sufficiently express an intention to make the literal fulfilment of such a thing [a promissory condition], it will be.

  1. (2)  Goodlife Foods v Hall Fire Protection Ltd (2018);4

  2. (3)  Lord Toulson in Impact Funding Ltd v Barrington Support Services Ltd (2016);5

  3. (4)  Homburg Houtimport BV v Agrosin Private Ltd (‘The Starsin’) (2003), Lord Steyn (‘I would respectfully also echo … Commercial men must be given the utmost liberty of contracting. They must be left free to decide on how to allocate commercial risks’);6

  4. (5)  Crédit Suisse Asset Management LLC v Titan Europe 2006-1 plc (2016), Arden LJ referring7 to the ‘fundamental principle of English contract law, known as the principle of party autonomy’.

2.06  The decision in North Midland Building Ltd v Cyden Homes Ltd (2018)8 provides a vivid application of the freedom of contract principle. Here a contractor was held to be liable to pay liquidated damages for delay in completing the project even though the delay was equally the result of the employer’s conduct. The Court of Appeal considered that the contractual language was clear and unambiguous and that no issue of public policy could be discerned which would justify nullifying or qualifying that language.

‘No Oral Modification’ Clauses and Freedom of Contract.

2.07  A controversial ‘application’ of the freedom of contract principle occurred in Rock Advertising Ltd v MWB Business Exchange Centres Ltd (2018). Here Lord Sumption declared that freedom of contract (he employed the synonymous phrase ‘party autonomy’) empowers the parties to bind themselves as to the manner in which the contract might be effectively varied, by requiring such a variation to be in writing. As noted at [5.29], there is conceptually much to be said for the converse analysis: that freedom of contract enables the parties to resile even from such an attempt at requiring formality before variations can be effected. Lord Sumption said:9

(p. 23)

[11] … Party autonomy operates up to the point when the contract is made, but thereafter only to the extent that the contract allows. Nearly all contracts bind the parties to some course of action, and to that extent restrict their autonomy. The real offence against party autonomy is the suggestion that they cannot bind themselves as to the form of any variation, even if that is what they have agreed. There are many cases in which a particular form of agreement is prescribed by statute: contracts for the sale of land, certain regulated consumer contracts, and so on. There is no principled reason why the parties should not adopt the same principle by agreement.

2.08  This decision is clearly English law, although some might have conceptual misgivings whether the Supreme Court was justified in sweeping aside the long-established perception that freedom of contract is a continuing capacity to revise an agreement, including contractual provisions purporting to fetter (at least formally) the mode of giving effect to consensual variations.10

Judicial Fidelity to the Parties’ Agreement.

2.09  It is fundamental that the court must respect the terms of a contract entered into freely by consenting parties of full capacity. The court’s legal duty is to show respect for the words chosen by the parties. It must refrain from illegitimately rewriting the agreement. Without such fidelity, civil proceedings cannot be properly adjudicated, whether by courts or arbitral tribunals.

2.10  For example, Lord Mustill in Charter Reinsurance Co Ltd v Fagan (1997) said11 that a court must not: ‘force upon the words a meaning which they cannot fairly bear’, because that would be ‘to substitute for the bargain actually made one which the court believes could better have been made’. He added:

Particularly in the field of commerce, where the parties need to know what they must do and what they can insist on not doing, it is essential for them to be confident that they can rely on the court to enforce their contract according to its terms.

2.11  And in Procter and Gamble Co v Svenska Cellulosa Aktiebolaget SCA (2012) Moore-Bick LJ said:12

[T]he starting point must be the words the parties have used to express their intention and in the case of a carefully drafted agreement of the present kind the court must take care not to fall into the trap of re-writing the contract in order to produce what it considers to be a more reasonable meaning.

2.12  Similarly, the courts recognize that they must be very slow to insert (allegedly) tacit terms into contracts, especially where the context involves a carefully formulated set of written terms. In Philips Electronique Grand Publique SA v British Sky Broadcasting Ltd (1995) Sir Thomas Bingham MR said:13 ‘It is because the implication of terms is so potentially intrusive that the law imposes strict constraints on the exercise of this extraordinary power.’

Freedom of Contract: Qualifications.

(p. 24) 2.13  The parties’ exercise of their contractual powers is subject to these five overarching limitations:

  1. (1)  public policy (chapter 16) (including inability to contract out of frustration based on supervening illegality [26.56]);

  2. (2)  the parties’ inability to exclude liability for fraud or duress at Common Law [11.143];

  3. (3)  statutory regulation of adhesion clauses, for example, exclusion clauses; such clauses are often presented on a take-it-or-leave-it basis [22.39]); and

  4. (4)  matters of personal capacity (age restrictions, mental disability, or the need for a company, or artificial legal entity, to be properly constituted) (chapter 8); and

  5. (5)  inability at Common Law to create a penalty consequent on breach [27.69].

Restraint of Trade Doctrine.

2.14  Jonathan Parker J in Panayiotou v Sony Music Entertainment (1994) considered14 at length the tension between the public policy interest in freedom of contract and the public policy against enforcing contracts which are unacceptably in restraint of trade.15

Contractual Estoppel.

2.15  Freedom of contract has been invoked, for example, to support ‘contractual estoppel’, on which [2.63].16 First Tower Trustees Ltd v CDS (Superstores International) Ltd (2018) [11.150] contains an important judicial re-examination of the legitimate scope of contractual estoppel.

Standard Clauses.

2.16  It must also be noted that freedom of contract, allied with the unwillingness of English law to make an overt assessment of the parties’ relative bargaining power [15.16], can lead to harsh clauses being inserted in favour of one party.17

2.17  Hugh Collins has said that the process of inferring consent by accession to standard form contracts is the most important feature of the objective principle.18



2.18  The court will assess the parties’ (or prospective or putative parties’) language or conduct according to its outward meaning or appearance.19

(p. 25) 2.19  The following quotation is seminal: ‘[T]he judicial task is not to discover the actual intentions of each party; it is to decide what each was reasonably entitled to conclude from the attitude of the other.’20

2.20  Lord Clarke said in RTS Flexible Systems Ltd v Molkerei Alois Muller GmbH and Co KG (2010):21

Whether there is a binding contract between the parties and, if so, upon what terms … depends not upon their subjective state of mind, but upon a consideration of what was communicated between them by words or conduct, and whether that leads objectively to a conclusion that they intended to create legal relations and had agreed upon all the terms which they regarded or the law requires as essential for the formation of legally binding relations. [Adding]:22 … English law generally adopts an objective theory of contract formation, ignoring the subjective expectations and the unexpressed mental reservations of the parties. Instead the governing criterion is the reasonable expectations of honest sensible businessmen.

2.21  And Blackburn J said in Smith v Hughes (1871):23

If, whatever a man’s real intention may be, he so conducts himself that a reasonable person would believe that he was assenting to the terms proposed by the other party, and that other party upon that belief enters into the contract with him, the man thus conducting himself would be equally bound as if he had intended to agree to the other party’s terms.

Pervasive Application.

2.22  The objective principle applies to any communication (or implicit understanding) or interaction between parties, or the parties and third parties, concerning the contract or its negotiation. The contexts include the following:

  1. (1)  formation; including intent to create legal relations,24 and formalities;25

  2. (2)  terms implied in fact [18.34];

  3. (p. 26) (3)  the presumptive exclusion of extrinsic evidence to add to, subtract from, vary, contradict a document (in accordance with the parol evidence rule), unless the text is shown not to been intended by the parties to express the totality of their agreement [17.20];

  4. (4)  incorporation of terms [17.52];

  5. (5)  whether a collateral warranty has been given [17.31];

  6. (6)  whether there has been a misrepresentation, express or implied [11.01] to [11.69];26

  7. (7)  whether a threat was objectively sufficiently potent [13.10];

  8. (8)  application of the doctrine of shared mistake [12.06];27

  9. (9)  affirmation as a bar to rescission [11.76];

  10. (10)  breach, for example, the test for an implicit renunciation [24.10];

  11. (11)  the election to terminate for breach or to affirm the contract [24.209];28

  12. (12)  interpretation [20.03]; including the delineation of categories of evidence required to illuminate the ‘factual matrix’ [20.57];29

  13. (13)  rectification [21.33];

  14. (14)  implied consensual termination [23.08];

  15. (15)  whether a party was acting as an agent for an undisclosed principal; the objective principle makes this submission an uphill struggle [2.38].30

2.23  As for (1), the issue, first, whether a party has made an offer in error and, secondly, whether this was apparent to the other party are discussed in accordance with the objective principle in Crest Nicholson (Londinium) Ltd v Akaria Investments Ltd (2010) [3.89].

2.24  The objective principle is especially prominent in context (12), interpretation of written contracts. This is because a written contract is a shared text (even if in reality it has been entirely shaped by one party). It follows that neither party can claim to be the addressee: the document is addressing them jointly.

2.25  As for context (13), rectification, the role of the objective principle has been reconsidered in FSHC Group Holdings Ltd v GLAS Trust Corporation Ltd (Rev 1) (2019).31 Common mistake rectification requires proof of an ‘outward expression’ which has been communicated ‘between them’: the quest is for an underlying shared subjective intention (‘the same actual intention with regard to the relevant matter’) on which the parties have reached consensus.

Rationale for Objective Principle.

2.26  The objective principle is based on numerous considerations:

(p. 27)

  1. (1)  it protects an addressee (and third parties) against the surprise and injustice which would result if the communicating party’s true but non-apparent intentions or private meanings were instead to govern; and

  2. (2)  promotes certainty and predictability; and

  3. (3)  promotes out-of-court settlement by the parties: guided by this objective criterion, the parties are more likely to be correct in predicting the manner in which the courts will interpret disputed conduct and words; and

  4. (4)  facilitates adjudication, because it would be hopeless for the courts to seek to discover, many months or years after the relevant facts occurred, whether a party’s words or conduct had been intended by him in some sense different from their apparent meaning.

2.27  Sir George Leggatt identifies32 four benefits in adopting the objective approach to contractual interpretation (notably in the context of construing written contracts):

  1. (1)  it gives ‘content to contractual obligations even in circumstances which the parties did not specifically envisage’;

  2. (2)  it enables ‘a party to predict with a reasonable degree of certainty … how its provisions will be interpreted, without having to probe or be concerned about whether the other party shares this understanding’;

  3. (3)  third parties can ‘ascertain the meaning of contractual provisions’ even though they were not ‘privy to the actual intentions’ of the parties;

  4. (4)  lawyers and judges can ‘ascertain the meaning of a contractual provision on the basis of relatively little information and without the need for an extensive and expensive factual inquiry’.

Test One: ‘Fly-on-the-Wall’: Neutral Objectivity.

2.28  Where the parties have agreed a shared text or set of words, the court will interpret that agreement by adopting the reasonable and objective perspective of a neutral bystander or disinterested third party.

Test Two: Objectivity from the Representee’s Perspective.

2.29  In general, the court will consider matters from the perspective of a person in the position of the representee, sometimes taking into account that party’s particular circumstances (notably in the context of formation of contracts, or a party’s response to the other’s breach). And thus the objective test might take into account, for example, whether the addressee is (known by the other party to be) a sophisticated trader or a complete commercial ingénu. According to this, the criterion is how the communication would be understood by ‘a reasonable representee in the [relevant context] and with the known characteristics of the actual representee’.33

(p. 28) 2.30  It is submitted that courts should be slow to dilute the objective approach by having undue regard to the particular knowledge or mental characteristics of a person engaged in commerce. For example, a court34 in Singapore, when examining the ‘reasonable ground’ test of liability under the Singaporean equivalent of section 2(1) of the Misrepresentation Act 1967, has unnecessarily complicated the inquiry by suggesting that the subjective awareness of the representor should be material, and that an objective assessment can be imposed upon that subjective state of affairs. The author at [11.106] criticizes this approach, which does not appear to be the English approach to this issue.35

2.31  Although promisee-objectivity enables the addressee to rely safely on the other’s outward language or conduct, proof of concrete detrimental reliance is not required. It is enough that the addressee has assumed that the objective meaning of the words would operate; that is, cognitive reliance is sufficient.36

2.32  Sometimes both tests (ie test one and two, as just explained) are mentioned in the same case but without differentiation. For example, in Hadley v Kemp (1999) (the Spandau Ballet case) Park J first stated that the question whether an offer has been made is to be assessed objectively, from the perspective of a notional third party observer; but he then presented the issue of objectivity from the perspective of the reasonable offeree.37

True State of Affairs Perceived by Party: Objective Appearance Not Determinative.

2.33  However, the true state of the promisee’s mind might become relevant. As Andrew Smith J noted38 in Maple Leaf Macro Volatility Master Fund v Rouvroy (2009), one party could not insist on the objective meaning if he or she knew the true position or ‘had simply formed no view one way or the other’. But on the facts the judge was satisfied that in fact the relevant party had had no reason to second-guess, and had in fact not second-guessed, the objective appearance that the other side was signing an agreement on the understanding that it would create legally binding obligations (the signatory’s alleged subjective intention not to be intending to enter a binding contract thus became irrelevant, because it was inconsistent with the objective principle).

2.34  Similarly, Leggatt J in Blue v Ashley (2017) said:39 ‘[64] There is, at least arguably, a limitation on the objective nature of the test where one party’s subjective intention is actually known to the other.’

2.35  But in the Maple Leaf case, emphasis upon objectivity was reinforced on appeal, where Longmore LJ remarked:40

I would not myself accept that the appellants’ subjective intentions have any relevance to the questions whether and when there came to be a binding contract. It is trite law that, (p. 29) although no contract can be made without an intention to be legally bound, that intention has to be ascertained objectively, not by looking into the parties’ minds.

2.36  With respect, that comment does not really address the point which Andrew Smith and Leggatt JJ were contemplating. Although party Y is entitled in general to rely on the objective meaning or appearance of party X’s words or conduct, including assessment of X’s intention, if Y has a clear contradictory perception, and that coincides with the true state of affairs, there is no sound reason for Y to be entitled to rely on that which, ex hypothesi, was not Y’s real understanding of the relevant circumstances (and see, similarly, the snapping up cases at [3.187]).

Objective Principle Qualified: Bad Faith Failure to Point Out Special Types of Mistake (‘Snapping Up’).

2.37  Where, to the knowledge of the other party, a party makes an offer by mistake, or mistakenly proposes terms, the other party cannot take advantage of this mistake. It is not enough, however, that the mistake concerns the quality of the subject-matter or its unwarranted value [3.195].

Undisclosed Principal.

2.38  Another context in which the objective principle does not operate is the curious, but well-established, doctrine that a contract between Y and Z might involve non-disclosure by Y of a subsisting agency relationship between X and Y. This is examined at [10.39]. Here it is enough to note Leggatt J’s elegant analysis in in Magellan Spirit ApS v Vitol SA (‘The Magellan Spirit’) (2016)41 of this doctrine as an exception to the general principle of objectivity.

Proof of an Oral Contract: Objectivity Supplemented by Subjective Evidence.

2.39  In Blue v Ashley (2017) Leggatt J said42 that it is legitimate to receive ‘evidence of the subjective understanding of the parties’ in order to determine whether an oral agreement ‘objectively … was reached and, if so, what its terms were and whether it was intended to be legally binding’. But the position concerning agreements made wholly in writing is quite different [20.26].

The Contractual Bond Principle


2.40  The contractual bond principle43 (pacta sunt servanda) has two limbs: (i) the contract remains binding even though performance becomes difficult; and (ii) neither party (p. 30) has an unilateral power to resile from the contract or to alter its terms, unless there is a term, express or implied, enabling a party to give notice of the termination of the contract (and) or the power to make unilateral alteration has been expressly conferred under the contract. Both aspects receive strong supported in English law. More generally, pacta sunt servanda (the maxim that promises should be kept) was invoked by Lord Mustill when recognizing a species of consumer protective damages in Ruxley Electronics and Construction Ltd v Forsyth (1996).44

The First Limb: No General Power to Relieve Against Bad, Harsh, or Imprudent Bargain.

2.41  Under the strict approach of English law, parties cannot escape bargains except in extreme circumstances, where the contract becomes impossible, illegal, or its very foundation has been annihilated by a change of circumstances. However, the fact that a contract becomes more difficult or expensive or less advantageous for a party to perform is not enough to release that party from the obligation, or to excuse this default, or to cause the contract to be terminated for frustration. Nor can the court modify contracts because of hardship or difficulty encountered during performance. As Lord Radcliffe noted in Bridge v Campbell Discount Co Ltd (1962), ‘the courts of equity never undertook to serve as a general adjuster of men’s bargains’.45 Thus Equity cannot be invoked to mend a hard bargain: ‘It is trite that equity will not rewrite an improvident contract where there is no disability on either side’, as Lord Hodson said in White and Carter (Councils Ltd v McGregor (1962).46 And Viscount Simonds said in Bridge v Campbell Discount (1962):47 ‘I must dissent … from the suggestion that there is a general principle of equity which justifies the court in relieving a party to any bargain if in the event it operates hardly against him.’

2.42  Equitable relief against forfeiture of a possessory or proprietary interest, whether in land or some other form of property, forms an exception to Equity’s insistence that bargains be upheld.48

(p. 31) 2.43  In Triple Seven v Azman Air Services (2018) Peter MacDonald Eggers QC, emphasized49 the need for that doctrine to be applied restrictively. Earlier, Lord Atkin had also observed in Bell v Lever Bros (1932), in the context of the doctrine of mistake:50

[this restrictive approach] can be supported on the ground that it is of paramount importance that contracts should be observed, and that if parties honestly comply with the essentials of the formation of contracts—i.e., agree in the same terms on the same subject-matter—they are bound, and must rely on the stipulations of the contract for protection from the effect of facts unknown to them.

Force Majeure Clauses.

2.44  Provision can be made in the contract, by insertion of force majeure clauses, to achieve a consensual modification of this strict regime. But such clauses tend not to be applied so as to offer commercially unacceptable relaxation of parties’ obligations (see the cases examined at [26.01]).

The Second Limb: No Unilateral Retreat, Termination, or Alteration.

2.45  It is axiomatic that a party cannot resile from an agreement once it has been formed by his or her assent, or where that party has acceded to a subsisting agreement by becoming an additional party. But to this general rule there is a statutory exception: in distance and off-premises contracts between a ‘trader’ and a ‘consumer’ for the supply of certain goods and services, the consumer enjoys rights of cancellation within a fourteen-day period.51 As for unilateral termination of contracts, this topic is examined in the context of, respectively, cancellation clauses [24.89] and termination of contracts of indefinite duration [23.01].

2.46  In general, a party is not at liberty unilaterally to revise the terms or content of the agreement for that party’s benefit unless there is a term (express or implied) permitting this. In Cavanagh v Secretary of State for Work and Pensions (2016) Laing J held52 that the employer lacked a unilateral power to end the relevant arrangement. It would appear that the relevant arrangement would remain binding on the employer for the remainder of the relevant individual’s employment.

Deeds and Guarantees.

2.47  Indeed there is a special rule in respect of certain written contracts: a deed or guarantee or other written instrument which is unilaterally and ‘materially’ altered without the other party’s permission is rendered void.53

Clauses Permitting Unilateral Alteration.

2.48  Some agreements expressly permit a party unilaterally to vary the rate of payment, or other contractual incidents, but such powers will be subject to implied constraints.54 In Bates v Post Office Ltd (No 3: Common Issues) (2019) (p. 32) Fraser J examined55 a provision in a contract which enabled the Post Office unilaterally to change the terms of the contract between it and sub-post masters. The clause had the potential to operate in an ‘onerous and unusual’ manner. Therefore, it would be incumbent on the Post Office to bring variations clearly to the notice of the other side. Similarly, in Cantt Pak Ltd v Pak Southern China Property Investment Ltd (2018), Barling J noted56 a term which permitted a party unilaterally to set a date which would make ‘time of the essence’.

2.49  The Consumer Rights Act 2015 renders it likely that a term will be unfair if it confers various unilateral powers exercisable by a trader operating to the prejudice of a consumer.57

Agreed Variations.

2.50  The corollary of the proposition that a contract cannot be unilaterally varied unless there is an express or implied term so permitting is that the law will give effect to a binding consensual variation (and limited effect to words or conduct founding an estoppel [6.74]).



2.51  Estoppel is not confined to contractual contexts. There are many forms of estoppel which can affect the operation of both substantive rights and evidential or procedural matters. Within the contractual sphere estoppel comprises various Common Law and equitable doctrines which operate in a flexible manner to ensure that, in the interest of commercial fair dealing or ‘good faith’ ([2.69] and chapter 19). The essence of estoppel is that a party (or prospective contractual party) cannot unfairly deviate from understandings or assumptions which (i) that party has induced or encouraged in the other party, or (ii) which that party knew that the other party held, or (iii) which the parties have informally shared or explicitly agreed.

Estoppel Not a Cause of Action, Unless Proprietary Estoppel is Made Out.

2.52  It is established in English law that only proprietary estoppel (see text below at (5)) can supply a cause of action.59 The other species of estoppel, notably, estoppel by representation, promissory estoppel, estoppel by convention, and contractual estoppel, operate in an auxiliary (p. 33) or defensive manner. Consistent with this, in Combe v Combe (1951) the Court of Appeal, including Denning LJ, held60 that promissory estoppel operates as a shield and not a sword. It does not establish an independent cause of action. It merely furnishes a defence. Unrequested detrimental reliance on another’s promise does not generate a contract: consideration (or a deed) must be shown to support the initial contract. Therefore, promissory estoppel in England (the position is different in Australia)61 is not an independent cause of action: it is not a substitute for consideration to support such an initial promise. And so, in England (as distinct from the United States), an agreement to give money to a charity does not become binding merely because the charity detrimentally relies on the promise.62

2.53  However, estoppel by representation and promissory estoppel can be used by a claimant in England to overcome some other impediment to his claim. As Robert Goff J explained63 in Amalgamated Investment & Property Co Ltd v Texas Commerce International Bank Ltd (1982), estoppel, including estoppel by representation and promissory estoppel, can assist a claimant to make good his claim, but only by supplementing a basic cause of action rooted (i) in the provision of consideration or (ii) founded perhaps on a deed.64

2.54  It should be noted, however, that proprietary estoppel (see text at (5) below) can be used as an independent cause of action.65 But proprietary estoppel is confined to situations where the representee has been induced detrimentally to rely in the belief that he has, or will shortly acquire, rights in, or in respect of, the representor’s land (or the representor has unconscionably acquiesced in that misunderstanding).

Types of Estoppel.

2.55  The eight main66 types of estoppel will now be listed.

(1)  Estoppel by Representation.

2.56  This applies if one party makes a statement by words (or sometimes by conduct) of past or present fact (but not a promise).67 The representation indicates that the other party should be assured that something has happened or is presently the case, and the representee must then have relied on the statement. The representor can be prevented by law (‘estopped’) from acting inconsistently with his statement. Representations of law are included.68 The requirement that a representation must be clear and unequivocal (p. 34) was considered in detail by Andrew Burrows QC, Deputy High Court Judge, in Harry Greenhouse v Paysafe Financial Services Ltd (2018).69 Although the essence of estoppel is that the representee relies on the other party’s statement, Goff J in ‘The Post Chaser’ (1982) held that the court can decide that there is insufficient reliance to justify estoppel.70 This type of estoppel, although not a cause of action, can be used by a claimant in order to supplement a cause of action which would otherwise not be satisfied.71

(2)  Promissory Estoppel.

2.57  Such a promise or representation concerns the future, for example, a creditor’s promise that a debtor will have more time to pay, or that he will be relieved from the remainder of his debt [6.74]. On the need for a promise to be clear and unequivocal see, the Harry Greenhouse case, above.

(3)  Estoppel by Convention.

2.58  Even in the absence of clear representations, the court can infer, on the basis of the parties’ interactive conduct, that they have concurred in treating a subsisting transaction as valid, or as having a particular effect or application. This type of estoppel does not require a specific representation. Instead the essence of estoppel by convention is coincident consensual interaction, not necessarily articulated. And thus this doctrine concerns an outward course of conduct which evidences or varies an agreement.72 There have been numerous judicial encapsulations of estoppel by convention: notably in this73 and the next note,74 and Chitty (and other (p. 35) commentary).75 There must be some pattern of visible conduct which indicates a shared assumption.76 No such conduct can arise merely from a pair of matching assumptions lodged metaphysically in the parties’ minds. For example, finding estoppel by convention on the facts, in Stevensdrake Ltd v Hunt (2017) Hamblen LJ identified77 no fewer than five exchanges between the parties which evidenced such a communication and shared assumption (the court also said78 that an appellate court will defer to a trial judge’s factual determination on this point). Unconscionability must also be found: that is, unless the estoppel is given effect, there would be palpable injustice on the facts.79

Effects of Estoppel by Convention.

2.59  This type of estoppel does not give rise to a cause of action.80 Thus estoppel by convention does not operate as a substitute for a contractual cause of action founded on consideration or a deed, but instead it acts in an auxiliary fashion.81 That is to say, estoppel by convention can operate to clear the way for a contractual, or other, cause of action to be made out.82 And thus, the defendant bank in the Amalgamated Investment case (below) could have used the estoppel to buttress a contractual claim on the guarantee. But the estoppel would not by itself found an action: consideration or a deed must exist independently of the estoppel which evidences that agreement. This mirrors the restriction, acknowledged in Combe v Combe (1951)83 on the operation of both estoppel by representation and promissory estoppel.

2.60  The effect of a successful plea of estoppel by convention might be to enlarge the rights which arise under an agreement, as the Court of Appeal confirmed84 in Rivertrade Ltd v EMG Finance Ltd (2015). Where this estoppel operates to vary an agreement, the relevant variation might have continuing effect.85


(p. 36) 2.61  Estoppel by convention cannot be used to circumvent a statutory prohibition upon contracting out of a protective set of rules.86

Estoppel by Convention and Entire Agreement Clauses.

2.62  There is inconclusive judicial discussion whether an entire agreement clause87 precludes a plea based on (pre-contractual) estoppel by convention (on entire agreement clauses and implied terms [18.130]; on such clauses and misrepresentation [11.161]; and on such clauses and rectification [21.10]). An ‘entire agreement’ clause is a stipulation in the main contract stating that the parties agree to exclude from their agreement any prior or external assurances or warranties or promises: and so the parties’ contractual obligations are to be found only within the four corners of the written contract and not in any side or prior agreement. Hamblen J in Dubai Islamic Bank v PSI Energy Holding Co (2011) inclined88 to the view that an entire agreement clause did not bar a plea based on estoppel by convention. The supporting argument in favour is that an entire agreement clause is intended to preclude agreements deliberately made, although not incorporated into the contractual document, whereas an estoppel by convention arises rather more by mutual inadvertence, in the sense that the parties did not engage deliberately and explicitly in formulating their understanding. The counterargument is that an entire agreement clause operates to nullify any form of prior or extrinsic understanding or agreement, including the consensus supporting estoppel by convention. Of course, the wording of the entire agreement clause is crucial.

(4)  Contractual Estoppel.

2.63  This enables parties to agree that specified past facts or events have or have not occurred. A party to such an estoppel is then precluded from making assertions or claims inconsistent with the agreed version of events, but First Tower Trustees Ltd v CDS (Superstores International) Ltd (2018)89 [11.150] contains an important revision of the effects of this type of estoppel, and there is a large literature.90

(5)  Proprietary Estoppel.91

(p. 37) 2.64  This type of estoppel arises where a person (party B) spends money improving (or otherwise acts to his detriment vis-à-vis) party A’s land in the mistaken assumption that party B has, or will acquire, rights in that land, and either: party A made a representation which induces that mistake or he acquiesces in party B’s mistake. This form of estoppel is exceptional because it can supply a basis of claim for party B, the representee, that is, it can constitute an independent cause of action, which is actionable by the representee without the need to show a bargain supported by consideration or a deed. And thus proprietary estoppel (unlike estoppel by representation or estoppel by convention or promissory estoppel) does not operate merely as a defence.

(6)  Estoppel by Silence or Acquiescence.92

2.65  Estoppel by silence or acquiescence can arise where a particular context imports a duty to point out to the other a misapprehension concerning that other party’s legal rights. (Estoppel by silence is distinct from estoppel by acquiescence in the context of proprietary estoppel, on which [2.64] above.)

Evaluation of Estoppel by Silence.

2.66  It is submitted that great care is required in the possible development of the elusive and dangerously seductive notion of estoppel by silence. A supporting triumvirate of Lords Wilberforce and Bingham and Sir Bernard Rix is impressive.93 But this doctrine needs to be applied with extreme caution. Estoppel by silence can only be applied if there is a duty to speak in the relevant context. A duty to speak is hard to ascribe, given English law’s preference for active representations. The higher courts would do well to pronounce either negatively on this doctrine or to confine it within the strictest possible limits.

(7)  Res Judicata.94

2.67  This concerns the preclusive effect of judicial decisions between the parties. Its effect is to bring about ‘claim or issue preclusion’, that is, the doctrine prevents claims (‘cause of action estoppel’) or issues (‘issue estoppel’) from being re-litigated between the same parties (including the doctrine of merger95 and the extension of this preclusive principle in the rule in Henderson v Henderson).

(8)  Apparent Authority.

(p. 38) 2.68  In the law of agency, it is established that a principal is liable to a third party where he has represented to that third party, or to the relevant class of third parties, that an agent has authority, on which the third party has acted by entering into a transaction purportedly with the principal via the agent’s intervention [10.31]. Chitty comments that ‘the doctrine is said to be an application of the estoppel principle, but it is a somewhat weak one, the normal rules being leniently applied, particularly in the contractual context as regards reliance on the representation’.96 However, the fact that the third party’s reliance turns out to be beneficial to that party, because it acquires the right to sue the principal and perhaps because the transaction is otherwise commercially advantageous, should not detract from the essential ‘estoppel model’, namely an alteration of position induced by a representation. The better view is presented in Anson where the editors say the doctrine of apparent or ostensible authority ‘is really an application of the principle of estoppel, for estoppel means only that a person is not permitted to resist an inference which can reasonably be drawn from that person’s words or conduct’.97 The learned editors then note that estoppel in this context presupposes that the principal must make the representation; that the third party must rely on the representation that there is agency authority to support the proposed transaction; the true position, namely the absence of, or restricted scope of, authority must not be known to the third party. In Freeman & Lockyer v Buckhurst Properties (Mangal) Ltd (1964),98 which is a (arguably the) leading case on this doctrine, Pearson and Diplock LJJ referred to it as founded on estoppel principles, and the point was repeated in 2006 in another court of Appeal discussion.99

Good Faith and Fair Dealing

The Two Meanings.

2.69  The main discussion of this principle is in chapter 19, where it is noted that ‘good faith’ (and fair dealing)100 can be used (i) to denote an organizing or overarching (p. 39) principle linking a miscellany of legal doctrines (in this sense it is referred to as a ‘Doctrinal Common Thread’) or (ii) it might refer to a generic implied duty to perform in good faith. It is (ii) which will involve letting the genie out of the bottle. English law is highly resistant to the latter: there is no general norm that contracts must be performed in good faith, and it is virtually unthinkable that English courts would adopt such a sweeping general requirement.

2.70  But it is arguable, and in a sense uncontroversial, that ‘good faith’, in the first sense (see (i) above), that is, referring to notions of fair dealing, is a pervasive feature of English contract law. There is a long tradition of ethical sensitivity within the English case law. In this spirit, Sir Frederick Pollock in (1881) spoke of the law of contract as the legal system’s ‘endeavor … to establish a positive sanction for the expectation of good faith which has grown up in the mutual dealings of [men and women] of average right-mindedness’.101 Even so, this is a ‘latent’ principle, in the sense that the courts have yet to formulate a general principle under this rubric.

Doctrines Exemplifying Sensitivity to Good Faith.

2.71  The following is a list (not necessarily exhaustive) of the many contexts in which English courts have implicitly acted on a principle of good faith or fair dealing (even though there is no articulated general principle of good faith and thus this is arguably only a ‘latent’ principle):

  1. (1)  protection where one party has unconscionably acquiesced in the other’s mistake [3.187];

  2. (2)  rectification, notably based on unilateral mistake unconscionably acquiesced in by bad faith party [21.35];

  3. (3)  specific duties to disclose [11.174];

  4. (4)  refusal of specific performance where the claimant has employed the element of surprise in circumstances not consistent with ‘good faith’ [6.23];102

  5. (5)  the doctrines of promissory and proprietary estoppel in Equity, waiver, estoppel by representation, and estoppel by convention [2.51];

  6. (6)  fiduciary duties: the duties of fair dealing imposed on agents and other fiduciaries103 when they contract with their principals, beneficiaries, or other protected persons [11.191];

  7. (7)  equitable relief against forfeiture of proprietary or possessory interests [24.115];

  8. (8)  the general principle that equitable relief will be withheld if the applicant has behaved shabbily and so lacks ‘clean hands’ [29.04]; that is, discretionary refusal of specific performance and injunctions;

  9. (9)  rescission for misrepresentation [11.12];

  10. (10)  rescission for undue influence (chapter 14);

  11. (11)  rescission for unconscionability (chapter 15);

  12. (12)  duress (chapter 13);104

  13. (p. 40) (13)  decisions denying that a party has a right to terminate a contract where this would be a wholly disproportionate response to the relevant breach [24.100];

  14. (14)  the penalty rule [27.69];

  15. (15)  ‘corrective construction’ based on the ICS/Chartbrook principles governing interpretation of written contracts [20.83];

  16. (16)  frustration (chapter 26); this is a questionable instance of ‘justice’ or ‘good faith’; sweeping references to ‘fairness’ or ‘justice’ in this context are unhelpful, as explained at [26.50];

  17. (17)  good faith underpins the ascription of duties not to prevent the other’s performance, based on the implied term of (i) cooperation105 or (ii) avoidance of stultifying conduct.106

2.72  Related to the point made at (16), but more generally, occasionally good faith can be seen to operate residually, as a compass to verify the soundness of the proposed outcome of the case. For example, Hildyard J said in Lehman Brothers International (Europe) (In Administration) v Exotix Partners LLP (2019): ‘it seems to me that this result accords with both overall commercial good sense and commercial morality.’107

The Compensation Principle

Nature of the Compensation Principle.108

2.73  This principle requires that contractual damages must represent true compensation. This means that they must be (i) compensatory and cannot be punitive109 (for the various ‘Measures of Compensation’, see two paragraphs below) and (ii) they must represent true compensation. Point (ii) will now be explained.

2.74  Various points ramify from the second of these propositions. Contractual damages:

  1. (1)  will not be awarded where the claimant has not suffered any substantial loss;

  2. (2)  the award cannot exceed the claimant’s true loss;

  3. (3)  damages cannot be awarded more than once for the same loss;

  4. (4)  compensation cannot be sought in successive claims, that is, in tranches, but must be sought in a single action and awarded in a single judgment;

  5. (p. 41) (5)  damages cannot be claimed by a person on behalf of another, except in limited exceptional situations where the law is satisfied that the damages will reach the true victim once even though initially awarded to the claimant;

  6. (6)  compensation can only be awarded to protect the claimant’s minimum expectation, where the defendant’s obligation contained an element of choice or discretion;

  7. (7)  damages can be reduced to take account of a failure to mitigate;

  8. (8)  compensation can be reduced to reflect contributory negligence, but only where the obligation breached is a duty of care, and there is a concurrent duty in the tort of negligence;

  9. (9)  damages cannot be awarded in respect of loss which is too remote or the loss sought lies outside the scope of the defendant’s duty.

2.75  Elements (1) to (9) of the ‘compensation principle’ apply equally to damages in the law of tort, whether the wrong involves negligence, deceit, or inducement of breach of contract (or some other ‘economic tort’), or conversion. Contractual and tortious causes of action might arise concurrently on the same facts, but the defendant cannot be ordered to pay damages more than once for the same loss suffered by the claimant, nor recover damages exceeding the amount of that party’s loss.

Compensation for Substantial Loss.

2.76  The general position is that the innocent party will be entitled to compensation where breach110 has caused substantial loss; that is, harm which the law recognizes as recoverable. In the absence of proof of substantial loss, the claimant is confined to nominal damages. There is no judicial award of punitive damages in English contract law [28.36].

Measures of Compensation.

2.77  There are various species or ‘measures’ of loss recognized for breach of contract, notably (see chapter 28 generally): expectation interest loss, that is, loss of bargain damages which aim to place the claimant in the position in which he would have been situated if the breach had not occurred; reliance loss damages which indemnify the claimant for expenses incurred and now lost as a result of the breach; loss of a chance damages, awarded to reflect the extent to which it was possible that the claimant might have achieved a particular gain (if the breach had not occurred); ‘cost of cure’ or ‘reinstatement’ damages, enabling the claimant to finance rectificatory work, or to be reimbursed for such work if already carried out; ‘negotiating damages’ which compensate for the claimant’s loss of opportunity to charge the defendant for infringing specially protected contractual rights.

Limits to the Compensatory Principle.

2.78  There are three limits:

  1. (1)  the compensatory principle does not invalidate a deposit, which can be forfeited even if it does not reflect the payee’s loss (but damages in addition to the deposit can be awarded, if the payee has suffered loss over and above the amount of the deposit) [27.119];

  2. (2)  nor will the compensatory principle invalidate a liquidated damages claim, even though the amount in fact exceeds the claimant’s actual loss, provided the liquidated damages clause is not a penalty [27.69];

  3. (p. 42) (3)  an award of damages is not the appropriate remedy where:

    1. (a)  the breach involves non-payment of a debt; the creditor is then entitled to sue for the sum owed; there is no need to show personal loss; it is enough that the sum is owed and that the claimant is the creditor, to whom payment is due (chapter 27);

    2. (b)  sometimes the appropriate remedy for breach will be a coercive order, sanctioned ultimately by contempt of court proceedings [29.56], for specific performance [29.01] or an injunction [29.30]; the final order of specific performance is a mandatory injunction to compel performance, and such an order is the primary relief sought in the context of agreements to transfer land for consideration, or to transfer shares in a private company; an injunction is readily available to require a party to desist from breaching a negative undertaking, that is, a promise whereby the defendant is required to refrain from doing something; a leading example of such an undertaking is an employee’s promise not to compete with the employer (provided the covenant does not infringe the restraint of trade principle in its scope or duration [16.60]);

    3. (c)  another remedy which might be awarded without an accompanying claim for damages is a declaration [29.75];

    4. (d)  there is an exceptional power to award an account of the profits made by breach of the contract, but this jurisdiction has not gathered momentum since its recognition [29.67].

Legal Usage.

2.79  The courts and Parliament employ language which directly invokes the concept of true and deserved compensation. Here are some examples:

  1. (1)  in Ruxley Electronics and Construction Ltd v Forsyth (1996)111 the claimant’s (tactical) undertaking to spend the cost of cure damages on repairs made no difference, because the trial judge had found that he lacked any real intention to rebuild the swimming pool, and the principle is that a claimant ‘cannot be allowed to create a loss, which does not exist, in order to punish the defendants for breach of contract’;112

  2. (2)  Lord Toulson in Bunge SA v Nidera BV (2015) said:113

[85] The fundamental compensatory principle makes it axiomatic that any method of assessment of damages must reflect the nature of the bargain which the innocent party has lost as a result of the repudiation… [86] … I see no virtue in such circumstances in the court attempting some form of retrospective assessment of prospective risk when the answer is known. To do so would run counter to the fundamental compensatory principle.

  1. (3)  In C & P Haulage v Middleton (1983)114 Ackner LJ said:

It is not the function of the courts where there is a breach of contract knowingly, as this would be the case, to put a plaintiff in a better financial position than if the contract had been properly performed. In this case the defendant who is the plaintiff (p. 43) in the counterclaim, if he was right in his claim, would indeed be in a better position because … had the contract been lawfully determined as it could have been in the middle of December, there would have been no question of his recovering these expenses.

  1. (4)  Section 5 of the Contracts (Rights of Third Parties) Act 1999 prevents the defendant in breach of contract from being at risk of ‘double jeopardy’ for the same loss, that is, liability to the promise at Common Law and liability to the third party, suing in its own name under the 1999 Act (as noted at [9.79]).

Compensation Is Not the Only Game in Town.

2.80  Compensation receives a large amount of attention in textbooks, judgments, theoretical discussion, lecture halls, and examinations. But the system of obtaining compensation is slow and complicated. This is true in most legal systems. Therefore, it behoves the legal advisor to counsel the client to contemplate use of deposits and liquidated damages clauses. Furthermore, debt claims are in fact the main type of remedy sought as a result of contractual default. A debt claim is not a claim for compensation, but for satisfaction of an obligation to transfer pecuniary value.(p. 44)


1  PS Atiyah, The Rise and Fall of Freedom of Contract (OUP 1979); S Smith (ed), Atiyah’s Introduction to the Law of Contract (6th edn, OUP 2006); HG Beale, Mistake and Non-disclosure of Facts: Models for English Contract Law (OUP 2012) 77–78; A Bell, ‘Excluding Exclusion Clauses: Judicial and Statutory Techniques, Freedom of Contract and Public Policy’ in S Degeling, J Edelman, and J Goudkamp (eds), Contract in Commercial Law (Thomson Reuters 2016) ch 18; R Brownsword, Contract Law: Themes for the Twenty-First Century (2nd edn, 2006) ch 3 (for an updated version, also by Brownsword, see M Furmston (gen ed), The Law of Contract (6th edn, LexisNexis 2017) ch 1, section B); Chitty on Contracts (HG Beale, gen ed, 33rd edn, Sweet and Maxwell 2018) 1-031 to 1-040; C Fried, Contract as Promise: A Theory of Contractual Obligation (2nd edn, OUP 2015); J Gordley, The Philosophical Origins of Modern Contract Doctrine (Clarendon Press 1991); D Kimel, From Promise to Contract (OUP 2005) ch 5; J Morgan, Contract Law Minimalism (Cambridge University Press 2013), notably ch 8 (‘The Limited Capacity of Contract Law’); L Mulcahy, Contract Law in Perspective (5th edn, Routledge-Cavendish Publishing 2008); Anthony Ogus and WH van Boom (eds), Juxtaposing Autonomy and Paternalism in Private Law (Hart Publishing 2011); SA Smith, Contract Theory (OUP 2004); MJ Trebilcock, The Limits of Freedom of Contract (Harvard University Press 1997).

2  (1875) LR 19 Eq 462, 465 (heard at first instance).

3  (1876) 1 QBD 183, 187.

4  [2018] EWCA Civ 1371, [2018] BLR 491 at [99] (Gross LJ).

5  [2016] UKSC 57, [2017] AC 73 at [38].

6  [2003] UKHL 12, [2004] 1 AC 715 at [57].

7  [2016] EWCA Civ 1293 at [28].

8  [2018] EWCA Civ 1744, [2018] BLR 565, 180 Con LR 1 at [39] and [47].

9  [2018] UKSC 24, [2019] AC 119 at [11].

10  The Rock case was applied in NHS Commissioning Board (known as NHS England) v Vasant [2019] EWCA Civ 1245, [2020] 1 All ER (Comm) 799 at [32] ff.

11  Both passages, [1997] AC 313, 388 (HL).

12  [2012] EWCA Civ 1413 at [22].

13  [1995] EMLR 472, 481–82.

14  [1994] EMLR 229, at 320–21.

15  The same tension was noted by Gross LJ in Proactive Sports Management Ltd v Rooney [2011] EWCA Civ 1444, [2011] 2 All ER (Comm) 815, [2012] IRLR 241 at [145].

16  As noted by J Braithwaite, ‘The Origins and Implications of Contractual Estoppel’ (2016) 132 LQR 120, 130–33.

17  The matter is addressed directly in Part 2, Consumer Rights Act 2015, and its antecedents. See also remarks of Lord Denning MR in George Mitchell (Chesterhall) Ltd v Finney Lock Seeds Ltd [1983] QB 284, 296–300 (CA).

18  HG Collins, The Law of Contract (4th edn, CUP 2003) 119 (and see the literature there cited at fnn 6 and 7); and see A Robertson, ‘The Limits of Voluntariness in Contract’ (2005) 29 Melbourne Univ LR 179; Hobhouse LJ in AEG (UK) Ltd v Logic Resource Ltd [1996] CLC 265, 278 (CA); and Dillon LJ in Interfoto Picture Library Ltd v Stiletto Visual Programmes Ltd [1989] QB 433, 438 (CA).

19  Detailed overviews: J Cartwright, Formation and Variation of Contracts: The Agreement, Formalities, Consideration and Promissory Estoppel (2nd edn, Sweet and Maxwell 2018) 3-301 to 3-12; M Furmston and GJ Tolhurst, Contract Formation: Law and Practice (2nd edn, OUP 2016) 1.07 to 1.16; G McMeel, The Construction of Contracts: Interpretation, Implication and Rectification (3rd edn, OUP 2017) ch 3.

Academic analysis: M Chen-Wishart, ‘Contractual Mistake, Intention in Formation and Vitiation: The Oxymoron of Smith v Hughes’ in JW Neyers, R Bronaugh, and SGA Pitel (eds), Exploring Contract Law (Hart Publishing 2009) 341; Paul S Davies, ‘Construing Commercial Contracts: No Need for Violence’ in M Freeman and F Smith (eds), Law and Language: Current Legal Issues 2011 (OUP 2013) ch 26, at 446–47; T Endicott, ‘Objectivity, Subjectivity and Incomplete Agreements’ in J Horder (ed), Oxford Essays in Jurisprudence (Fourth Series, OUP 2000) 159; D Friedmann, ‘The Objective Principle and Mistake and Involuntariness in Contract and Restitution’ (2003) 119 LQR 68; J Getzler, ‘Interpretation, Evidence, and the Discovery of Contractual Intention’ in Degeling, Edelman, and Goudkamp (eds), Contract in Commercial Law, ch 7; D Goddard, ‘The Myth of Subjectivity’ [1987] LS 263; W Howarth, ‘The Meaning of Objectivity in Contract’ (1984) 100 LQR 265 and ‘A Note on the Objective of Objectivity in Contract’ (1987) 103 LQR 527; Sir George Leggatt (as he then was), ‘Making Sense of Contracts: the Rational Choice Theory’ (2015) 131 LQR 454; D McLauchlan, ‘A Better Way of Making Sense of Contracts’ (2016) 132 LQR 576 (and by same author), ‘Objectivity in Contract’ (2005) 24 UQLJ 479, and ‘Common Intention and Contract Interpretation’ [2011] LMCLQ 30; D McLauchlan, ‘Refining Rectification’ (2014) 130 LQR 83, 88–90); McMeel, Construction (2017) ch 3; J Morgan, Great Debates in Contract Law (3rd edn, Palgrave Publishing 2020) 1–7; JM Perillo, ‘The Origins of the Objective Theory of Contract Formation and Interpretation’ (2000) 69 Fordham L Rev 427; JR Spencer, ‘Signature, Consent and the Rule in L’Estrange v Graucob’ [1973] CLJ 104; R Stevens, ‘The Meaning of Words and the Intentions of People’ in Degeling, Edelman, and Goudkamp (eds), Contract in Commercial Law, ch 9; J Vorster, ‘A Comment on the Meaning of Objectivity in Contract’ (1987) 103 LQR 274; SM Waddams, The Law of Contracts (7th edn, Thomson Reuters 2017) [141] to [147]; see also, from an American perspective, T Joo, in L DiMatteo and others (eds), Commercial Contract Law: Transatlantic Perspectives (CUP 2014) ch 3; for other references, McMeel, Construction (2017) ch 3 fn 1.

20  McCutcheon v David MacBrayne Ltd [1964] 1 WLR 125, 128 (HL); Lord Reid, quoting Gloag on Contract (2nd edn, W Green Publishing 1929) 7.

21  [2010] UKSC 14, [2010] 1 WLR 753 at [45].

22  ibid, at [47].

23  (1871) LR 6 QB 597, 607.

24  Novus Aviation Ltd v Alubaf Arab International Bank BSC [2016] EWHC 1575 (Comm), [2017] 1 BCLC 414 at [54] to [59], Leggatt J.

25  Rabiu v Marlbray Ltd [2016] EWCA Civ 476, [2016] 1 WLR 5147 at [65] to [68].

26  On implied representations, Marme Inversiones 2007 SL v Natwest Markets plc [2019] EWHC 366 (Comm) at [123] (Picken J).

27  For a trenchant review of the topic, Dana Gas PJSC v Dana Gas Sukuk Ltd [2017] EWHC 2928 (Comm), [2017] 2 CLC 735, [2018] 2 Lloyd’s Rep 177 at [57] to [65] (Leggatt J).

28  Notably, Vannin Capital PCC v RBOS Shareholders Action Group Ltd [2018] EWHC 2821 (Ch) at [105] to [113], Joanna Smith QC), citing Vitol SA v Norelf Ltd (‘The Santa Clara’) [1996] AC 800, 810 letter H to 811 letter B (Lord Steyn) and Shell Egypt West Manzala GmbH v Dana Gas Egypt Ltd [2010] EWHC 465 (Comm) at [31] and [32] (Tomlinson J).

29  Hildyard J in Lehman Brothers International (Europe) (In Administration) v Exotix Partners LLP [2019] EWHC 2380 (Ch), [2020] Bus LR 67, [2001] 1 All ER (Comm) 635 at [112].

30  Magellan Spirit ApS v Vitol SA (‘The Magellan Spirit’) [2016] EWHC 454 (Comm), [2017] 1 All ER (Comm) 241, [2016] 2 Lloyd’s Rep 1 at [15], [18], [28] (Leggatt J).

31  [2019] EWCA Civ 1361, [2020] Ch 365 at [176].

32  Leggatt, ‘Making Sense of Contracts: the Rational Choice Theory’. There has been a rejoinder to Leggatt’s analysis. McLauchlan, ‘A Better Way of Making Sense of Contracts’, contends that the law is concerned to give effect not, of course, to internal psychological intention, but to (the parties’ coincident) apparent intention, assessed from the ICS informed vantage point of the reasonable reader; and McLaughlan notes that Leggatt has jettisoned all reference to party intention.

33  For the latter formulation see Hamblen J in Cassa di Risparmio v Barclays Bank [2011] EWHC 484 (Comm), [2011] 1 CLC 701 at [215], adopting Neuberger LJ in Kyle Bay Ltd v Underwriters Subscribing Under Policy No 01957/08/01 [2007] EWCA Civ 57, [2007] 1 CLC 164 at [30] and [31], who in turn had followed Mance LJ in MCI WorldCom International Inc v Primus Telecommunications Inc [2004] EWCA Civ 957, [2004] 2 All ER (Comm) 833 at [30], by Mance LJ, again in the context of misrepresentation. Mance LJ had linked this to the ICS principles of interpretation [20.18], where it is necessary to consider the objective meaning of a text against the background of all the background knowledge which a reasonable person would have had at the time of the contract’s formation; see also Marme Inversiones 2007 SL v Natwest Markets plc [2019] EWHC 366 (Comm) at [117] ff, Picken J.

34  RBC Properties Pte Ltd v Defu Furniture Pte Ltd [2014] SGCA 62, [2015] 1 SLR 997.

35  See Bridge LJ in the Howard Marine case (1978), English Court of Appeal at [11.105]).

36  See Lord Diplock’s discussion in Paal Wilson & Co A/S v Partenreederi Hannah Blumenthal (‘The Hannah Blumenthal’) [1983] 1 AC 854, 915–16 (HL).

37  [1999] EMLR 589, 621, 623.

38  [2009] EWHC 257 (Comm), [2009] 2 All ER (Comm) 287, [2009] 1 Lloyd’s Rep 475 at [229]; the entire discussion (ibid, at [216] to [254]) is a lucid examination of the objective principle.

39  [2017] EWHC 1928 at [64], citing see Novus Aviation Ltd v Alubaf Arab International Bank BSC [2016] EWHC 1575 (Comm), [2017] 1 BCLC 414, [56] (and see Novus case at [54] to [59] for further discussion).

40  [2009] EWCA Civ 1334, [2010] 2 All ER (Comm) 788 at [17].

41  [2016] EWHC 454 (Comm), [2017] 1 All ER (Comm) 241, [2016] 2 Lloyd’s Rep 1 at [15] to [36].

42  [2017] EWHC 1928 at [64].

43  Chitty (2018) 1-041 to 1-043; David Hughes Parry, The Sanctity of Contracts in English Law (Hamlyn Lectures) (Stevens Publishing 1959); HG Beale, ‘Adaptation to Changed Circumstances …’ in Binding Force of Contract (Budapest Institute for Legal and Administrative Sciences of the Hungarian Academy of Sciences 1991), at sections 12 and 13, discussing (predominantly) variation arrangements within the construction law field. Variation: general observations on variation, Neil Andrews, Contract Rules: Decoding English Law (Intersentia Publishing 2016), Articles 122 to 124; Cartwright: Formation (2018) ch 9, 10; Chitty (2018) sections 4.9 (Discharge and Variation of Contractual Duties) and 4.10 (Part Payment of a Debt’), ch 22 (Discharge by Agreement), section 25.1 (Merger), section 25.2 (Alteration or Cancellation of a Written Instrument); B Coote, ‘Variations Sans Consideration’ (2011) 27 JCL 307; R Halson, ‘The Modification of Contractual Obligations’ (1991) 44 CLP 111; Law Revision Committee, 6th Interim Report, ‘The Statute of Frauds and the Doctrine of Consideration’ (1937, Cmd 5449); variation in the context of building contracts more generally, M Sergeant and M Wieliczko, Construction Contract Variations (Informa Law 2014).

Long-term contracts, J Adams and R Brownsword, ‘Contract, Consideration and the Critical Path’ (1991) 53 MLR 536, 542; J Bell, ‘The Effect of Changes in Circumstances on Long-Term Contracts’ in DR Harris and D Tallon (eds) Contract Law Today (OUP 1989); K Dharmananda and L Firios (eds), Long Term Contracts (Federation Press 2013) (collection of comparative essays); A Downes, ‘Nominalism, Indexation, Excuse and Revaloration: A Comparative Survey’ (1985) 101 LQR 98, 104–08; K Lewison, Interpretation of Contracts (7th edn, Sweet and Maxwell 2020) 6.18; W Lorenz, ‘Contract Modification as a Result of Change of Circumstances’ in J Beatson and D Friedmann (eds), Good Faith and Fault in Contract Law (OUP 1995) ch 14; Ian Macneil, ‘The Many Futures of Contract’ (1974) 47 Southern California Law Review 691; ‘Contracts: Adjustments of Long-Term Economic Relations under Classical, Neo-Classical and Relational Contract Law’ (1978) 72 Northwestern University Law Review 854; McKendrick, ‘The Regulation of Long-Term Contracts in English Law’ in Beatson and Friedmann (eds), Good Faith and Fault in Contract, at 323 ff; E Schanze, ‘Failure of Long-Term Contracts and the Duty to Re-negotiate’ in FD Rose (ed), Failure of Contracts: Contractual, Restitutionary and Proprietary Consequences (Hart Publishing 1997) ch 10 (and the response by G Samuel, ibid, ch 11); long-term contracts and frustration: J Beatson, ‘Increased Expense and Frustration’ in FD Rose (ed), Consensus ad Idem: Essays in the Law of Contract in Honour of Guenter Treitel (Sweet and Maxwell 1996) 121; E McKendrick, ‘Frustration, Restitution and Loss Adjustment’ in AS Burrows (ed), Essays on Restitution (OUP 1991) 147; Morgan, Great Debates in Contract Law, ch 6.

44  [1996] AC 344, 360 (HL).

45  [1962] AC 600, 626 (HL).

46  ibid, 445.

47  [1962] AC 600, 614 (HL). Similarly, Lord Neuberger said in Arnold v Britton [2015] UKSC 36, [2015] AC 1619 at [20]: ‘it is not the function of a court when interpreting an agreement to relieve a party from the consequences of his imprudence or poor advice. Accordingly, when interpreting a contract a judge should avoid re-writing it in an attempt to assist an unwise party or to penalize an astute party.’ And in ParkingEye Ltd v Beavis [2015] UKSC 67, [2016] AC 1172 at [13], Lords Neuberger and Sumption said: ‘Leaving aside challenges going to the reality of consent, such as those based on fraud, duress or undue influence, the courts do not review the fairness of men’s bargains either at law or in equity.’

48  On the latter point, the Supreme Court in Vauxhall Motors Ltd v Manchester Ship Canal Co Ltd [2019] UKSC 46, [2020] AC 1161 at [85] and [87] (Lady Arden).

49  [2018] EWHC 1348 (Comm), [2018] 2 Lloyd’s Rep 424 at [67] and [68] (Peter MacDonald Eggers QC).

50  [1932] AC 161, 224 (HL).

51  Consumer Contracts (Information, Cancellation and Additional Charges) Regulations 2013 (SI 2013/3134), Part 3, and Cancellation of Contracts made in a Consumer’s Home or Place of Work, etc Regulations 2008 (SI 2008/1816) (on the latter, Robertson v Swift [2014] UKSC 50, [2014] 1 WLR 3438).

52  [2016] EWHC 1136 (QB), [2016] ICR 826 at [43] to [35] (authorities considered), and [75] (conclusion on this point).

53  Habibsons Bank Ltd v Standard Chartered Bank (Hong Kong) Ltd [2010] EWCA Civ 1335, [2011] QB 943 at [34] (Moore-Bick LJ); McMeel, Construction (2017) 27.14 ff.

54  Chitty (2018) 38-312, 39-145 to 39-148; Lewison, Interpretation (2020) 14.04, 14.05; and see Neil Andrews, Contract Law (2nd edn, CUP 2015) 13.14, examining various cases, including Paragon Finance plc v Nash [2001] EWCA Civ 1466, [2002] 1 WLR 685 at [32] and [36] (implied term that the lender must exercise without dishonesty, capriciousness, or for an improper purpose an express power to vary the rate of interest payable by its customer); R Hooley, ‘Controlling Contractual Discretion’ [2013] CLJ 65; MG Bridge, ‘The Exercise of Contractual Discretion’ (2019) 135 LQR 227.

55  [2019] EWHC 606 (QB) at [986] to [1001]; also noting another commercial case where variations would operate from time to time, Stretford v Football Association [2006] EWHC 479 (Ch), [2007] Bus LR 1052.

56  [2018] EWHC 2564 (Ch) at [82].

57  Schedule 2, Part 1, at paragraphs 3, 7, 8, and 11 to 17, Consumer Rights Act 2015.

58  Monographs, see Bibliography, Part II, section (17). Judicial Analysis: the following passages should be consulted: (i) on the core idea of estoppel, Blindley Heath Investments Ltd v Bass (also known as Dixon v Blindley Heath Investments Ltd) [2015] EWCA Civ 1023, [2017] Ch 389 at [80] (Hildyard J, giving the judgment of the court, Longmore, Jackson LJJ agreeing); (ii) on promissory estoppel, Hughes v Metropolitan Railway Company (1877) 2 App Cas 439, 448 (Lord Cairns LC); (iii) Robert Goff J in Amalgamated Investment & Property Co Ltd (in liquidation) v Texas Commerce International Bank Ltd [1982] QB 84, 103–04; and (iv) for another general statement of estoppel at large, Amalgamated Investment & Property Co Ltd (in liquidation) v Texas Commerce International Bank Ltd [1982] QB 84, 122 (CA) (Lord Denning MR).

59  R Halson, Contract Law (2nd edn, Pearson Publishing 2013) 372 ff and R Halson, ‘The Offensive Limits of Promissory Estoppel’ [1999] LMCLQ 257; A Robertson, ‘Estoppels and Rights-Creating Events …’ in Neyers, Bronaugh, and Pitel (eds), Exploring Contract Law, 199; M Barnes, ‘Estoppels as Swords’ [2011] LMCLQ 372. See the Bibliography at section (17) ‘Estoppel’. See also, on Halson’s analysis, E McKendrick, Contract Law: Text, Cases, and Materials (9th edn, OUP 2020) 222–23.

60  [1951] 2 KB 215, 219–20 (CA). The same point was confirmed in Baird Textile Holdings Ltd v Marks and Spencer plc [2001] EWCA Civ 274, [2002] All ER (Comm) 737 (CA) at [35] to [39] (Morritt LJ) and [54] (Judge LJ); similarly, Newport City Council v Charles [2008] EWCA Civ 1541, [2009] WLR 1884 at [23], last sentence (Laws LJ). Lord Walker in Cobbe v Yeoman’s Row Management Ltd [2008] UKHL 55, [2008] 1 WLR 1752 at [85] (noted, J Getzler, (2009) 125 LQR 196) cited the Baird case without disapproval. Lord Walker made clear that he was hostile to an expansion of proprietary estoppel, fearing that it would produce commercial uncertainty (ibid, at [46] and [81]).

61  The High Court of Australia in Walton’s Stores (Interstate) v Maher (1988) 164 CLR 387 has rejected the Combe v Combe restriction (for comment, Halson, Contract Law, 377 ff; M Spence, Protecting Reliance (Hart Publishing 1999); the latter work is criticized by Peter Jaffey (book review) [2000] Restitution Law Review 458). The same result would not occur on such facts in England: eg, in Western Fish Products Ltd v Penwith District Council [1981] 2 All ER 204 (CA), WPP spent money on its own land in expectation of receiving planning permission from PDC, but it was held that proprietary estoppel did not arise in WFP’s favour because that party was not expecting that it had or would acquire any interest in PDC’s land.

62  Re Hudson (1885) 54 LJ Ch 811 (Pearson J); Re Cory (1912) 29 TLR 18 (Eve J); by contrast, in the United States, an informal promise to subscribe to charity is enforceable once the promisee has relied upon it: see Restatement of the Law Second, Contracts, s 90(2).

63  [1982] QB 84, 105 (and Brandon LJ in the Court of Appeal agreed, ibid, 131–32),

64  As for (ii), see Shah v Shah [2001] EWCA Civ 527, [2002] QB 35.

65  On this type of estoppel, Crabb v Arun District Council [1976] Ch 179 (CA).

66  On estoppel by deed, not treated here, M Barnes, The Law of Estoppel (Hart Publishing 2020) ch 4.

67  Jorden v Money (1854) 5 HL Cas 185; 10 ER 868.

68  Re Gleeds, Briggs v Gleeds [2014] EWHC 1178 (Ch), [2015] Ch 212 at [26] to [35] (Newey J).

69  [2018] EWHC 3296 (Comm) at [14] to [17], [38] to [40], [50] to [52].

70  [1982] 1 All ER 19, 25B–27.

72  Republic of India v India Steamship Co Ltd (‘The Indian Endurance’) (No 2) [1998] AC 878, 914–15 (HL) (Lord Steyn).

73  (1) Bristol Rovers (1883) Ltd v Sainsbury’s Supermarkets Ltd [2016] EWCA Civ 160 at [84] to [89] Floyd LJ (with whom Laws and McCombe LJJ agreed) set out the principles by reference to the following authorities: Republic of India v India Steamship Co Ltd (No 2) [1998] AC 878, 913 (HL) (Lord Steyn); The August Leonhardt’ [1985] 2 Lloyd’s Rep 28; The Vistafjord’ [1988] 2 Lloyd’s Rep 343 (CA); Hiscox v Outhwaite [1992] 1 AC 562 at 575 (CA) (Lord Donaldson); Amalgamated Investment & Property Co Ltd (in liquidation) v Texas Commerce International Bank Ltd [1982] QB 84 (CA); Troop v Gibson [1986] EGLR 1 (CA); the Troop case also received comment in Carnwath LJ’s judgment in the ING case, [2011] EWCA Civ 353, [2012] 1 WLR 472 at [64] sub-paragraph (ii); and in Blindley Heath Investments Ltd v Bass (also known as Dixon v Blindley Heath Investments Ltd) [2015] EWCA Civ 1023, [2017] Ch 389 at [101], see (2) immediately below;

  1. (2)  the Court of Appeal in Blindley Heath Investments Ltd v Bass (also known as Dixon v Blindley Heath Investments Ltd) [2015] EWCA Civ 1023, [2017] Ch 389 at [72] ff; where Hildyard J, giving the court’s judgment (Longmore, Jackson LJJ agreeing), conducted a historical survey of estoppel by convention, including reference to seminal Australian authorities; close attention should be paid to the passages, ibid, at [92] to [94] and [98]. The Court of Appeal, ibid, at [100] and [101] also upheld the trial judge’s finding that unconscionability or unfairness had been established;

  2. (3)  in Stevensdrake Ltd v Hunt [2017] EWCA Civ 1173, [2017] BCC 611, [2017] 4 Costs LR 781 at [60] and [61], Hamblen LJ, Briggs LJ agreeing, defined estoppel by convention by reference to a passage in Chitty (2018) 4–108.

74  (1) BBC Worldwide Ltd v Bee Load Ltd [2007] EWHC 134 (Comm) at [53] and [54] (Toulson LJ at first instance); Durham v BAI (Run Off) Ltd [2008] EWHC 2692 (QB), [2009] 4 All ER 26 at [267] and [268] (Burton J); (2) Carnwath LJ in ING Bank NV v Ros Roca SA [2011] EWCA Civ 353, [2012] 1 WLR 472 at [49], [55] to [74] (the discussion is binding because Stanley Burnton LJ indicated assent, ibid, at [76]); furthermore, even though Rix LJ reached the same result by reference to another form of estoppel (promissory estoppel), he too assented to Carnwath LJ’s analysis (ibid, at [85]) (see [2.65] below for Rix LJ’s alternative approach by reference to the doctrine of estoppel by silence); (3) HSM Offshore BV v Aker Offshore Partner Ltd [2017] EWHC 2979 (TCC), 175 Con LR 155 at [73] (Coulson J); in the context of a pension trust, in Re Gleeds [2014] EWHC 1178 (Ch), [2015] Ch 212 at [180] to [182], Newey J formulated the principles governing estoppel by convention, but he concluded (ibid, at [183] to [185]) that no joint understanding had arisen or been relied on; (4) in Bank Leumi (UK) plc v Phillip Robert Akrill [2014] EWCA Civ 907 at [55], Kitchin LJ said: ‘it is a necessary ingredient of such an estoppel that the shared assumption of the parties … should be expressly communicated between them’; that seems to be a repetition of the well-established requirement that the parties’ interaction should reveal a mutual understanding, based on either explicit communications or on conduct, such interaction mutually reinforcing the relevant assumption; it in this sense that the word ‘express’ is used, and it would be wrong to interpret ‘express’ as importing a need for actual words of expression.

75  Besides the expositions set out above, see the case law authorities cited in Chitty (2018), 2nd supplement 2020, 4-108, including comments in Crabbe v Townsend [2016] EWHC 2450 (Ch), [2017] WTLR 13 at [7] (John Martin QC). Commentary on Estoppel by Convention. See Chitty (2018) 4-108 to 4-115; T Brettel Dawson, ‘Estoppel and Obligation: The Modern Role of Estoppel by Convention’ (1989) 9 LS 16; KR Handley, Estoppel by Conduct and Election (2nd edn, Butterworths Publishing 2014) ch 8; S Wilken and K Ghalys, The Law of Waiver, Variation and Estoppel (3rd edn, OUP 2012) ch 10; McMeel, Construction (2017) ch 18; Lord Steyn, ‘Contract Law: Fulfilling the Reasonable Expectations of Honest Men’ (1997) 113 LQR 433, 440.

76  Republic of India v India Steamship Co Ltd (No 2) [1998] AC 878, at 914–15 (HL); Bridgewater v Griffiths [2000] 1 WLR 524, 530 (Burton J).

77  [2017] EWCA Civ 1173, [2017] BCC 611, [2017] 4 Costs LR 781 at [77] to [89].

78  ibid, at [75], [76], [90] (Hamblen LJ); [100] (Briggs LJ).

79  The element of a shared assumption was missing in Yuchai Dongte Special Purpose Automobile Company Ltd v Suisse Credit Capital (2009) Ltd [2019] EWHC 2580 (Comm), [2019] 1 Lloyd’s Rep 457; see comments at [84] and [85] by Christopher Hancock QC. ‘Unconscionability’ was absent in the Durham case [2008] EWHC 2692 (QB), [2009] 4 All ER 26 at [284], Burton J. But this element was present in Bristol Rovers (1883) Ltd v Sainsbury’s Supermarkets Ltd [2016] EWCA Civ 160 at [92] and [93], and in Blindley Heath Investments Ltd v Bass (also known as Dixon v Blindley Heath Investments Ltd) [2015] EWCA Civ 1023, [2017] Ch 389 at [100] to [102], and in Stevensdrake Ltd v Hunt [2017] EWCA Civ 1173, [2017] BCC 611, [2017] 4 Costs LR 781 at [96].

80  But, surprisingly, McMeel suggests otherwise, Construction (2017) 18.21 to 18.25.

81  For example, Stevensdrake Ltd v Hunt [2017] EWCA Civ 1173, [2017] BCC 611, [2017] 4 Costs LR 781 at [91] and [92] (Hamblen LJ).

82  Amalgamated Investment & Property case, [1982] QB 84, 132 (CA) (Brandon LJ).

83  [1951] 2 KB 215 (CA).

84  [2015] EWCA Civ 1295, [2016] 2 BCLC 226 at [48] and [50] (Kitchin LJ).

85  Bristol Rovers (1883) Ltd v Sainsbury’s Supermarkets Ltd [2016] EWCA Civ 160 at [84] to [93].

86  Keen v Holland [1984] 1 WLR 251 (CA) (protection under the agricultural holdings legislation).

87  Generally on entire agreement clauses, Deepak Fertilisers & Petrochemicals Corp v ICI Chemicals and Polymers Ltd [1999] 1 Lloyd’s Rep 387, 395 (CA) (noted by Gloster J in Six Continents Hotels Inc v Event Hotels GmbH [2006] EWHC 2317 (QB) at [49]); D McLauchlan, ‘The Entire Agreement Clause … ’ (2012) 128 LQR 521; M Barber, ‘The Limits of Entire Agreement Clauses’ [2012] JBL 486; E Peden and J Carter, ‘Entire Agreement and Similar Clauses’ (2006) 22 JCL 1; McMeel, Construction (2017) ch 26; Catherine Mitchell, ‘Entire Agreement Clauses’ [2006] 22 JCL 222.

88  [2011] EWHC 2718 (Comm) (see [72], [83], and [84] (not following Christopher Nugee QC in Sere Holdings Ltd v Volkswagen Group United Kingdom Ltd [2004] EWHC 1551 (Comm) at [25]); Gloster LJ in Shoreline Housing Partnership Ltd v Mears Ltd [2013] EWCA Civ 639, [2013] CP Rep 39 (agnostically) took the same view as Hamblen LJ; but these 2011 and 2013 decisions both concerned applications for summary judgment, so that the matter has yet to be authoritatively determined.

89  [2018] EWCA Civ 1396, [2019] 1 WLR 637 at [99] to [111]; Prime Sight Ltd v Lavarello [2010] EWCA Civ 1221, [2010] 2 CLC 705 at [30], [46] and [47] (on its facts, estoppel by deed: A Trukhtanov, ‘Receipt Clauses: From Estoppel by Deed to Contractual Estoppel’ (2014) 130 LQR 3).

90  Braithwaite, ‘The Origins and Implications of Contractual Estoppel’, 120 (ante-dating the important discussion by Leggatt LJ in the First Tower case [2018] EWCA Civ 1396, [2019] 1 WLR 637 at [99] to [111]). Braithwaite, ibid, 133–34, notes the difficulty of integrating contractual estoppel into an unified theory of estoppel, because this species of estoppel does not require detrimental reliance. But nor does estoppel by convention, category (3) above. At 146 Braithwaite convincingly suggests that contractual estoppel involves estopping a party from ‘denying a version of events that they previously agreed to, whether or not that version of events was true’. See also N Goh, ‘Non-reliance Clauses and Contractual Estoppel: Commercially Sensible or Anomalous?’ [2015] JBL 511. A Trukhtanov, Contractual Estoppel (Informa Law Publishing 2017); for a radical critique, G McMeel, ‘Documentary Fundamentalism in the Senior Courts: The Myth of Contractual Estoppel’ [2011] LMCLQ 185, and McMeel, Construction (2017) 26.52.

91  The principles governing proprietary estoppel were distilled by Lewison LJ in Davies v Davies [2016] EWCA Civ 463, [2016] P & CR 10 at [38] and [39]; as cited by Henderson LJ in Moore v Moore [2018] EWCA Civ 1140, [2019] 1 FLR 1277, [2019] WTLR 233 at [24] and [25]; and further considered in Guest v Guest [2020] EWCA Civ, [2020] 1 WLR 3480 at [47] to [53], [68] to [86] (Floyd LJ); and see B McFarlane, The Law of Proprietary Estoppel (2nd edn, OUP 2020).

92  ING Bank NV v Ros Roca SA [2011] EWCA Civ 353, [2012] 1 WLR 472 at [94] and [95], Rix LJ, cited Bingham J’s examination in Tradax Export SA v Dorada Cia Naviera SA (‘The Lutetian’) [1982] 2 Lloyd’s Rep 140, 157, of Lord Wilberforce’s analysis of estoppel by silence in Moorgate Mercantile Co Ltd v Twitchings [1977] AC 890, 903 (HL).