Need. A power of attorney is an expression of the will of both parties. In principle, the trustee needs to sign to express his consent to the entrustment, which will take effect once signed. However, if the trustee fails to sign, the act of the trustee showing the power of attorney to the third party can also be regarded as the recognition of the entrustment, and the entrustment will take effect. If the trustee cannot produce it, the trustee may terminate the entrustment at any time. As a client, if you want to ensure the entrusted matters, you'd better sign an entrustment agreement and ask the client to sign a power of attorney to avoid leaving hidden disputes. Article 490 of the Civil Code If the parties conclude a contract in the form of a contract, the contract is established when the parties sign, seal or press their fingerprints. Before signing, sealing or fingerprinting, one party has fulfilled its main obligations, and the contract is established when the other party accepts it. A contract shall be concluded in written form as stipulated by laws, administrative regulations or agreed by the parties. If the parties do not do this in writing, but one party has fulfilled its main obligations and the other party accepts it, the contract is established.

Legal objectivity:

civil law

Article 165

If the power of attorney is in written form, the power of attorney shall specify the agent's name, agency matters, authority and time limit, and shall be signed or sealed by the principal.

civil law

Article 166

If several persons are the same agent, unless otherwise agreed by the parties, they shall jointly exercise the agency right with others.

civil law

Article 167

If the agent knows or should know that the agency matters are illegal but still carries out the agency behavior, or if the principal knows or should know that the agent's agency behavior is illegal and does not raise any objection, the principal and the agent shall bear joint liability.