Professional Services of Australia Pty Ltd v Computer Accounting and Tax Pty Ltd [No 4]

The case involved Professional Services of Australia Pty Ltd, the appellant, and Computer Accounting and Tax Pty Ltd, the respondent. The dispute centred on the validity of an order made by the Federal Circuit Court of Australia, which had been appealed to the Full Court of the Federal Court. The appellant sought to appeal the orders made by the Federal Circuit Court, while the respondent argued against the appeal's validity. A third party, Computer Accounting and Tax (Vic) Pty Ltd, applied for leave to intervene in the appeal, arguing that it had a direct interest in the outcome due to its ownership of a company that was a party to the original proceedings. The third party also sought to vary an extracted order on the basis that there was an inadvertent or accidental omission.

The court had to determine whether the third party had a sufficient interest in the appeal to warrant intervention and whether the application to vary the extracted order was valid under the slip rule. The court needed to consider the criteria for granting leave to a non-party to intervene in an appeal, as well as the requirements for varying an order under the slip rule. Specifically, the court had to assess whether the omission in the extracted order was inadvertent or accidental, and whether it was in the interests of justice to vary the order.

The court held that the third party did not have a sufficient interest in the appeal to warrant intervention. The court found that the third party's interest was indirect and speculative, as it was not directly affected by the orders in question. The court also found that the application to vary the extracted order was not valid under the slip rule, as the omission was not inadvertent or accidental. The court held that the third party had not demonstrated that the omission was a mistake or oversight, and that it had not acted promptly to bring the error to the attention of the court. The court held that varying the order would not be in the interests of justice, as it would alter the outcome of the original proceedings.

The court dismissed the application for leave to intervene and the application to vary the extracted order. No further orders were made.