The Course of Events
25 On 14 June 1991, National Australia Trustees Ltd ('NAT'), the then trustee of the Southgate Trust, entered into an agreement to lease to IBM a portion of a building to be constructed in an area known as 'Southgate, South Melbourne' (the 'Agreement for Lease'). The terms and conditions of the proposed lease were set out in a schedule to the agreement (the 'Pro Forma Lease'). The Agreement for Lease also required the parties to perform and observe their respective obligations under the 'First Construction Agreement' and the 'Second Construction Agreement', both of which were to be executed simultaneously with the Agreement for Lease.
26 The First Construction Agreement recited that NAT, as lessor, had agreed to procure the completion and fitting out of the building at its own expense. NAT agreed to carry out certain fit-out works specified in the schedule at a cost which was not to exceed an amount calculated by reference to a formula. That amount, according to expert evidence, was in the order of $27 million.
27 A lease in terms of the Pro Forma Lease (the '1994 Lease') was ultimately executed on 29 April 1994 by Opalwood Pty Ltd, the then trustee of the Southgate Trust, as lessor and IBM as lessee. The 1994 Lease was for a term of one year commencing on 24 January 1994 in respect of the Premises which, as noted in [5] supra, comprised eighteen floors of Office Space, Store Rooms and Car Park. The annual rent was $10,519,740 for the Office Space; $97,920 for the Car Park; and $7,770 for the Store Rooms. The annual rent for the Office Space was apparently calculated on the basis of the sum of $420 per square metre per annum specified in the Agreement for Lease. As indicated at [20] supra, this was very much higher than the market rent for comparable office space when the Agreement for Lease was entered into in June 1991 ($240 per square metre per annum) and when the relevant lease renewals occurred, being January 2001 ($260 per square metre per annum) and January 2003 ($275 per square metre per annum) - see [52] and [53] infra. This discrepancy was attributable to the fact that the 'face rent' included an amount to recoup to the lessor the cost of the fit-out of the Premises - see [20] supra and [50] infra.
28 The 1994 Lease provided for options for a further thirteen terms, each of two years. The options could be exercised, either by the lessor or the lessee, except for the eighth further option and the eleventh further option, each of which could be exercised only by the lessee. Thus the minimum effective term of the lease, assuming the lessor exercised each of its options, was 15 years.
29 The lessor duly exercised the option in the 1994 Lease for a further two year term commencing on 24 January 1995. Opalwood Pty Ltd and IBM subsequently entered into a Deed of Renewal of Lease on 28 June 1995 providing for a two year lease commencing on 24 January 1995. The Deed of Renewal provided for the same annual rent as the 1994 Lease.
30 On 14 November 1995, Opalwood Pty Ltd contracted to sell the office development known as 'Southgate', including the Premises, to Perpetual Trustees Australia Ltd ('Perpetual'), as trustee of the Paladin Southgate Trust. The sale, which was completed on 20 December 1995, was subject to the lease of the Premises to IBM.
31 It appears that the lessor exercised its option for a further two year term commencing on 24 January 1997. During 1996, however, IBM and Perpetual negotiated with a view to executing a new lease substantially on the same terms as the 1994 Lease, but incorporating some minor variations.
32 On 16 March 1998 the parties executed the Subject Lease of the Premises for a two year term commencing on 24 January 1997. The definition of 'Demised Premises' in par (a) of the Definitions Clause of the Subject Lease included the fit-out undertaken by the lessor. The Subject Lease provided for the same annual rent of $10,519,740 as had hitherto applied for the Office Space. The annual rent for the Car Park was increased to $222,400, but remained the same ($7,770) for the Store Rooms. Clause A2 of the Subject Lease required the lessee to pay the rent reserved, the revised rent determined pursuant to cl C13 and any other moneys payable under the Subject Lease. Clause A3 required the lessee to pay or reimburse to the lessor the 'Operating Costs' calculated and payable in the manner specified in cl A4.
33 The Subject Lease made provision in cl C13 for review of the rent relating to the Office Space. A review could take place on the commencement date for each further term granted pursuant to the options granted by cl C14.
34 Clause C15 contained an acknowledgement by IBM that the terms and conditions set out in the Subject Lease and the agreements and deeds described in cl C15.3 contained the entire agreement between the parties. The agreements and deeds identified in cl C15.3 included the First Construction Agreement.
35 The lessor duly exercised the option for a further term of two years commencing on 24 January 1999, the fifth anniversary of the commencement of the 1994 Lease. On 3 December 1998, the parties executed a Deed of Renewal of Lease recording the renewal of the Subject Lease and specifying certain amendments to the lease to apply during the two year term. The annual rent for the Office Space, Car Park and Store Rooms remained unchanged from that applicable immediately prior to the renewal.
36 The Subject Lease was also renewed on 24 January 2001 and 24 January 2003, in each case apparently by the lessor exercising the option. Prior to the first renewal, Rreef had become the responsible entity and trustee of the Paladin Southgate Trust, succeeding Perpetual. Following the 2001 renewal, the parties executed a further Deed of Renewal of Lease, but did not do so until 11 November 2002. Similarly, following the 2003 renewal, the parties executed a Deed of Renewal of Lease, but not until 14 October 2003.
37 The 2002 Deed of Renewal provided that the lessor leased the Premises to IBM as lessee for a term of two years as from 24 January 2001. The annual rent specified in the 2002 Deed of Renewal for the Office Space remained as it was immediately prior to 24 January 2001 (that is, $10,519,740). The annual rent for the storage room also remained unchanged. However, the annual rent for the Car Park was increased as from January 2001 to $332,112, as a result of a review carried out pursuant to the terms of cl C16.6 of the Subject Lease. Presumably this review produced an increase because the annual rent for the Car Park stipulated in the Subject Lease was not substantially above market levels.
38 The 2003 Deed of Renewal of Lease took a similar form, adapted to take account of the renewal that had occurred as from 24 January 2001. The rent for the Office Space remained unchanged, as did the rent in respect of the Car Park and the Store Rooms.