In a matter involving disputed patents under the Patents Act 1978, ten judges of the Constitutional Court sat and there were five judges on each side whether to uphold or dismiss the appeal. Where there is no majority decision, the judgment of the lower court stands. Each party was ordered to pay their own costs.
This does mean that the ultimate winner also had the Pretoria High Court judge on their side so they were in the majority but it doesn’t help to decide what the correct legal position is.
The application related to whether an invention was patentable under the Patents Act and whether the matter could be heard at all because it was alleged the issue had already been decided in another court. Half the court found that the dispute could not be heard again and the other held to the opposite effect.
Fortunately, it is a matter more or less specific to its facts so the lack of a decision is not especially significant in South African law, except as a legal curiosity.