JUDGMENT

Abang Iskandar Abang Hashim PCA:

Introduction

[1] We heard this appeal on 14 February 2022 with 10 questions of law (QOL) granted at the leave stage for our determination. The 10 QOLs concern mainly issues of unjust enrichment; res judicata; limitation; constructive/implied trust; estoppel; frustration; reciprocal promises; and appellate jurisdiction. The 10 QOLs read:

(i) Whether the test for unjust enrichment is "act or delivery of thing that can be said to have done by the Plaintiffs which was not intended to be done gratuitously that had benefitted the defendants?

(ii) Whether res judicata applies to a 2nd action filed after the Federal Court in a 1st action has ruled it to be premature with unsatisfiled conditions precedent?

(iii) Whether the time ceases to run under the Sabah Limitation Ordinance ("SLO") during the duration of prosecution and appeal of a 1st action subsequently ruled by the Federal Court as premature and such time is excluded for filing a 2nd action?