Mosman Services Pty Ltd (ACN 079 350 744) (Suing in a Representative Capacity as Trustee of the Mosman Services Trust) v William James McDonald

Mosman Services Pty Ltd (ACN 079 350 744), suing in a representative capacity as Trustee of the Mosman Services Trust, brought proceedings against William James McDonald. The dispute involved claims for damages and an account of profits, among other things, arising from alleged breaches of fiduciary duty and the unauthorised use of confidential information. The case was heard in the Supreme Court of New South Wales. The central issue for the court was the apportionment of costs between the parties, considering the plaintiffs' overall success and the defendants' partial success on certain claims.

The court considered the principles relevant to the apportionment of costs in cases where one party achieves partial success. It examined the overall success of the plaintiffs in their primary claims, which led to their entitlement to substantial costs. However, the court also acknowledged the defendants' success on some claims, which mitigated the plaintiffs' entitlement. The court weighed these factors and concluded that the plaintiffs should be awarded 80% of their costs, recognising both the plaintiffs' success and the defendants' partial success.

In arriving at this decision, the court highlighted that the primary objective in cost apportionment is to achieve a fair and just outcome. It balanced the plaintiffs' overall success against the defendants' success on certain claims, leading to the determination that the plaintiffs should receive a significant, but not complete, proportion of their costs. The court's reasoning focused on ensuring that the costs awarded reflected the relative success of each party in the litigation.

The court ordered that the plaintiffs should be awarded 80% of their costs. This outcome recognises the plaintiffs' primary success while also considering the defendants' partial success, resulting in a balanced and equitable apportionment of costs.