" The then current Basic Rent as escalated pursuant to sub-paragraph (a) above [the Airbus Escalation] shall be further escalated pursuant to this sub-paragraph (b) on the first Basic Rent Payment Date and each third Basic Rent Payment Date thereafter as follows: if L [LIBOR] on such date is greater than the Base Rate [100 bp], the Basic Rent will increase by$325 for each basis point that L is greater than the Base Rate; or if on such date L is less than or equal to the Base Rate, the Basic Rent for the Rent Period will not be escalated in accordance with this sub-paragraph (b) "
" 22.2 … Alternatively, or in addition, Saudia is estopped by convention from contending otherwise by reason of a common assumption, established during the negotiation of the Lease Agreements. The common assumption was that the purpose of the LIBOR Escalation mechanism was to increase rent by reference to the highest LIBOR rate during the course of the Lease Agreements (i.e. that it would function as a ratchet). As to this estoppel by convention, the parties understood and accepted that: 22.2.1 the LIBOR Lease rates would impact upon the financing arrangements that the Claimants and Third Party would enter into, given the reliance on LIBOR by financer to set the terms of finance arrangements; 22.2.2 That finance costs would accordingly be directly impacted by increases in the LIBOR rate and that required related increases in the LIBOR Lease rates to reflect the impact on finance costs which the parties acknowledged would not necessarily be linear; 22.2.3 That LIBOR rates were low and had the potential to increase; 22.2.4 That Saudia would, consistently with its commercial objectives, receive a discounted rent amount from that originally proposed along with concessions regarding maintenance, at the outset 22.2.5 That in return for the Claimant and Third Party's concessions on rent and maintenance, the low LIBOR Rates in existence at the time and the non-linear impact on finance costs that would result from an increase in the LIBOR Rates, that the LIBOR Escalation would function as a ratchet. 23. As to the formation of this estoppel by convention, it was formed and communicated between the parties as follows: 23.1 The LIBOR Escalation mechanism was inserted following Saudia's insistence (through Mr Salah Al Jasser) on a significantly discounted Basic Rent: USD 640,000 for A330s, instead of the USD 850,000 originally proposed, and USD 318,000 for A320s, instead of the USD 385,000 originally proposed, as well as other concessions on maintenance. 23.2 The common understanding was reached, and communicated between the parties, at meetings between the parties from May-June 2015, including (i) a meeting at the offices of Mr Hashim Koshak (Saudia's then Head of Legal) with the attendance of Mr Abdullah Al Gahtani, Mr Ashraf Suleman, Mr Syed Bokhari and Mr Abdulgader Bujabair (from Saudia) and Dr Idriss Ghodbane and Mr Moulay Omar Alaoui of IAFC; and (ii) a meeting at the offices of Mr Saleh Al Jasser, attended by Mr Koshak and Mr Abdulrahman Al Tayeb of Saudia and Dr. Idriss Ghodbane and Mr Moulay Omar Alaoui of IAFC, at which the ratchet range was fixed. 23.3 The common understanding was further reflected in other communications between the parties, including in an email and attached 'commentary document' sent by Mr Koshak of Saudia to IAFC on26 May 2015 , in which Saudia expressed its understanding of the LIBOR Escalation consistently with the interpretation set out at paragraphs 7-8 above ."
" 52. In my judgment, the principles applicable to the assertion of an estoppel by convention arising out of non-contractual dealings, to be derived from Keen v. Holland, and the cases which comment upon it, are as follows: (i) It is not enough that the common assumption upon which the estoppel is based is merely understood by the parties in the same way. It must be expressly shared between them. (ii) The expression of the common assumption by the party alleged to be estopped must be such that he may properly be said to have assumed some element of responsibility for it, in the sense of conveying to the other party an understanding that he expected the other party to rely upon it. (iii) The person alleging the estoppel must in fact have relied upon the common assumption, to a sufficient extent, rather than merely upon his own independent view of the matter. (iv) That reliance must have occurred in connection with some subsequent mutual dealing between the parties. (v) Some detriment must thereby have been suffered by the person alleging the estoppel, or benefit thereby have been conferred upon the person alleged to be estopped, sufficient to make it unjust or unconscionable for the latter to assert the true legal (or factual) position ."
" 51. It may be helpful if I explain in my own words the important ideas that lie behind the first three principles of Benchdollar. Those ideas are as follows. The person raising the estoppel (who I shall refer to as "
"In the context of estoppel by convention, the question here is whether the party estopped actually (or as reasonably understood by the estoppel raiser) intended the estoppel raiser to rely on the subscription of the party estopped to their common view (as opposed to each, keeping his own counsel, being responsible for his own view)."
"… While it is possible that there may be some differences required by the relevant contractual or non-contractual context …, it would appear that the Benchdollar principles are being viewed as general principles applicable to estoppel by convention. It is significant in this respect, that the present edition of Spencer Bower: Reliance-Based Estoppel, 5th ed (2017), chapter 8, centres its whole analysis of estoppel by convention on the Benchdollar principles. Although it is unnecessary to decide this in this case - and we heard no submissions on it - there appears to be no good reason to confine them to non-contractual dealings. In my view, the five Benchdollar principles, with the Blindley Heath amendment to the first principle, comprise a correct statement of the law on estoppel by convention for contractual, as well as non-contractual, dealings ."
" 7. Final Reconciliation: There shall be a final reconciliation to apply in respect of all Aircraft relating to the changes in Lessee Requested SCN and the final escalation based on the Airbus Price Revision Formula, with the settlement of the final reconciliation taking place on the final Delivery of the last A320 Aircraft. 8. 2016 Escalation: For all Aircraft Delivered in 2016, the Airbus Price Revision Formula to be applied is 1.053228 ."
" Construed by reference to its language and the factual matrix, including but not limited to the fact that the post-2016 figures were not yet available from Airbus (as pleaded in paragraph 6 (d) above) and the designated formula itself, the MoU recorded and reflected the agreement between the parties to use only the Airframe Price Revision Formula, and not the Propulsion Systems Revision Formula "
" a. Pursuant to the commercial agreement reached at the meeting of8 August 2016 with Mr Saleh Al Jasser on behalf of Saudia, and in return for the parties agreeing that there would be no Event of Default in relation to Saudia's failure to provide unaudited financial statements for a 24-month period, Saudia agreed that the APRF in respect of all Aircraft deliveries would only include the Airframe Price Revision Formula, and not the Propulsion Systems Price Revision Formula, and that the subsequent month's formula would be used for each delivery. The price escalation indices used for the purposes of the Airframe Price Revision Formula are publicly available ."
" b. That agreement was reflected and recorded in writing (in respect of each Aircraft, and each amounting to a formal variation of each of the Lease Agreements) in: i. the fifty Lease Supplements, signed by Mr Al -Jasser as the then-Director General of Saudia, which set out the applicable APRF figure at paragraph 4; ii. paragraphs 7 and 8 of the MoU (as pleaded at paragraphs 6(d) and 10 above), which was signed by Mr Al-Jasser; and iii. paragraph 6(v) of and Appendix 1 to the fifty Notices of Assignment and paragraph 4(j) of the corresponding fifty Acknowledgements of Assignment of Sub-Lease, the latter of which were signed by Mr Al-Jasser ."
" c. In addition, or alternatively, Saudia is estopped by convention and/or by representation from resiling from the APRF figures which it agreed and paid, alternatively waived its right to advance to insist on any rival figure for APRF, by reason of: i. Saudia's conduct in signing the MoU, each of the fifty Lease Supplements and each of the fifty Acknowledgements of Assignment of Sub-Lease and/or its payment of invoices as pleaded at paragraphs 21 and 23 of the Particulars of Claim, amounts to a representation that it was agreeing to the APRF figures contained in those documents and actually invoiced, alternatively gave rise to a common understanding that Airbus Escalation was to be calculated on that basis. ii. The Claimants and Third Party have reasonably relied on that representation or common understanding, in that they have relied on the sum of prevailing rent payments in their interactions with banks, including in a refinancing agreement with Alinma Bank (as set out at paragraph 10 of their Response to the Request for Further Information dated9 April 2021 ). They would suffer detriment if Saudia were permitted to resile from that representation or common understanding, in that (inter alia) this would potentially require the restructuring of the financing agreements, and cause harm to their relationships with those banks (including Alinma Bank) ."
" The Claimants are also entitled to and claim in debt and/or damages for breach of contract (without prejudice to their right to claim further or alternative loss and damage in due course): … 37.3 Payment of all Late Payment Amounts in respect of Unpaid Amounts, in the sum of USD 364,086 (as at7 December 2020 ) …"
" In circumstances where the Lessors must pay Late Payment Amounts to charity: (i) They are not entitled to claim damages (as opposed to debt) for non-payment of those sums unless they allege and prove, as they have not, they had costs against which they could legitimately have retained portions of the Late Payment Amounts. (ii) Any order requiring Saudia to pay any Late Payment Amounts should require the Lessors to pay such payments over to charity in accordance with clause 4(f)(iii) ."
" The position is akin to one where a promise [sic] seeks specific performance of an obligation to pay a third party "