ChD 1 July 1988 Application by landlords National Westminster Bank (N) to strike out the claim by tenants Arnold and others (A), senior partners of Arthur Young McClelland and Moores , for a declaration seeking the construction of a rent review clause in a subunderlease . At the first review date the matter went to arbitration and the arbitrator held for A. On appeal by N, the ChD had allowed N`s appeal. A was refused leave to appeal and the CA held that it had not jurisdiction to entertain an appeal against the ChD`s refusal to certify a question of law which should be considered by CA (See National Westminster Bank plc v Arthur Young McClelland and Moores ). At the second review date A started a further set of proceedings claiming, inter alia, a determination as to the true construction of the review clause. N applied to strike out the claim on the basis that there was an issue of estoppel on the matter. A contended that issue estoppel was not an absolute doctrine and that, in exce