• If the agent has expressly or implied consented to personal liability.
• If the principal does not exist or has no capacity to contract (Kelner V. Baxter).
• If the agent had represented or held himself out as the principal.
• If the agent has exceeded his authority i.e. breach of warranty of authority.
• If the agent has executed a document ordered in his own name. (Schakv V. Anthony).
• If the agent signs a negotiable instrument in his own name.