How and when do I deliver a protest, and when is it invalid?

A protest must be in writing and identify the protestor, the protestee and the incident. Deliver it to the race office (or as the sailing instructions say) within the protest time limit, unless the protest committee decides there is good reason to extend it.

The time limit is two hours after the last boat in the race finishes for an incident observed in the racing area, or two hours after the relevant information is available for other protests. If the sailing instructions state a different time limit, that applies instead.

A protest is invalid if, among other things, it does not comply with the definition of Protest or rules 60.2 or 60.3, or if a boat alleges a breach of a Part 2 rule or rule 31 but was not involved in the incident or did not see it.

Source: Racing Rules of Sailing 2025-2028 with Australian Sailing prescriptions, rules 60.3 and 60.4.