By virtue of the foregoing, the appellants had sufficient basis, in terms of authenticity and content of the Unofficial Tax Notice, to raise some tax issues in the First Suit. In fact, we noted that they had attempted to do so in SUM 4540 and SUM 2425 but, for reasons unknown to us, they had not referred the court then to the Unofficial Tax Notice as well as the 22 September 2017 Letter. As mentioned, AIL had applied to amend the Reply in the First Suit to raise tax issues. The pertinent proposed amendment alleged that Mr Kam had represented and warranted that, “PT ARI did not have any subsisting or contingent tax liabilities in Indonesia” and that this representation was untrue and the warranty was broken because, “PT ARI had various tax liabilities to Indonesian authorities”. However, the application was disallowed because of the lack of particulars, which particulars were not provided despite the AR’s indication that they were needed. In fact, AIL had some particulars as shown by the 22 September 2017 Letter. Consequently, it was their own fault (as the Judge observed at [26] of the Judgment) that they did not succeed in their amendment application. In the circumstances, we agreed with the Judge’s finding that the attempts to include tax issues in the First Suit had been half-hearted. The appellants were therefore precluded from raising tax issues in the Second Suit. This evidence being sufficient to establish the appellants’ knowledge of the tax issues, it was unnecessary for us to deal with Mr Chang’s evidence about tax issues during the trial of the First Suit.