Margo v Gardner

On 14 April 1999, Margo served a summons against Gardner and OTR Mining Ltd. Mlambo J initially found in favour of Margo for approximately R15 million. Gardner appealed to the SCA, which succeeded on 28 March 2006, resulting in a reduced judgment against Gardner for R1,461,432 plus interest at 15.5% per annum from 1 September 1998 to date of payment. Gardner made two payments totaling R3,022,864 (R1,222,864 on 24 April 2006 and R1,800,000 on 23 September 2006). Gardner believed these payments settled the capital amount in full and that only costs remained outstanding. A dispute arose regarding the calculation of interest and costs. Margo issued a writ of execution on 7 December 2007 claiming R185,983 for balance of interest. Gardner launched an urgent application to suspend the writ, which was dismissed by Horwitz AJ on 28 February 2008. A second writ was issued on 3 October 2008 for R264,396.06 capital plus R82,749.02 interest. Gardner again challenged this, and Gyanda J found in his favour, ordering Margo to pay R5,615.83 to Gardner for overpayment and setting aside the second writ. Two conflicting judgments resulted, both relying on the Oneanate case but reaching different conclusions.

• Whether the in duplum rule applied to the calculation of interest on the SCA judgment debt
• Whether interest continues to accumulate pendente lite (during litigation)
• The meaning and consequences of suspension of the in duplum rule during litigation
• Whether the in duplum rule prevents interest from exceeding double the capital amount outstanding in a judgment

In case 511/09 (Gardner's appeal): The appeal was dismissed with costs, with the appellants ordered to pay costs jointly and severally. In case 564/09 (Margo's appeal): The appeal was upheld with costs. The order of the court a quo (Gyanda J) was set aside and substituted with an order dismissing the applications with costs, including costs reserved on 14 October 2008.

The in duplum rule is suspended pendente lite (during the pendency of litigation), which begins from service of the initiating process. Once a final judgment has been granted, interest may accumulate until it reaches double the capital amount outstanding in terms of that judgment. The suspension of the rule during litigation means that interest can accumulate beyond what would normally be the in duplum limit during the period proceedings are pending. Delays inherent in litigation cannot be attributed to litigants, and it would be unfair to penalize a creditor with the application of the in duplum rule while proceedings are pending. Where a court order does not provide for any interest ceiling and is unequivocal, effect must be given to it as it stands.

The Court noted that the cause of action makes no difference in the application of the in duplum rule, citing LTA Construction Bpk, Bellingan v Clive Ferreira & Associates CC, and Meyer v Catwalk Investments 354 (Pty) Ltd. The prohibition on interest in duplum rule is not limited to money-lending transactions but applies to all contracts arising from a capital sum owed which is subject to a specific rate of interest. The Court observed that the purpose or basis of the in duplum rule is twofold: to protect borrowers from exploitation by lenders who permit interest to accumulate, and to encourage plaintiffs to issue summons and claim payment of the debt speedily. The Court mentioned that a question was raised whether the issues dealt with in Horwitz AJ's judgment were res judicata, but found it unnecessary to decide that question. The Court also noted that a creditor is not prevented by the rule from collecting more interest than double the unpaid capital amount provided that he at no time allows the unpaid arrear interest to reach the unpaid capital amount.

This case provides important clarification on the application of the in duplum rule in South African law, particularly regarding its suspension during litigation. It confirms the principle established in Oneanate that the in duplum rule is suspended pendente lite, meaning interest can accumulate beyond double the capital amount during the period litigation is pending. The judgment reinforces that delays inherent in litigation should not penalize creditors by applying the in duplum rule during proceedings. It also clarifies that once a final judgment is granted, interest may continue to run until it reaches double the capital amount outstanding in terms of that judgment. The case demonstrates the practical application of the in duplum rule in commercial debt contexts and ensures that creditors are not unfairly prejudiced by litigation delays beyond their control.