The cannon of insurance contracts that states insurance policies are written by the insurer and therefore any ambiguity is interpreted against the insurer is called:

• Contra proferentem
• Installing sprinklers to reduce the severity of a fire loss
• Estoppel
• A company deciding not to manufacture a dangerous product to eliminate that risk entirely
• Reformation
• Setting aside reserves to self-insure against small losses
• Adhesion
• Purchasing insurance to transfer the financial risk of loss