contra proferentem
Meaning. An ambiguous term in a document is read against the party who drafted it or who relies on it.
The rule places the risk of unclear drafting on the party who chose the words. It is applied mostly to standard form contracts, insurance policies and exclusion clauses, where one side writes the terms and the other simply accepts them. An ambiguous exclusion in an insurance policy is read in favour of the insured.
It is a rule of last resort. The court first tries to find the meaning from the words and the contract as a whole; only if a real ambiguity remains does it read the term against the drafter. It cannot be used to create an ambiguity where the words are clear.
Example
Since “flood” in the exclusion clause could mean either river flooding or any water ingress, the term is read contra proferentem against the insurer who drafted it.