1, if the signature is the legal representative of the company, it is valid;

2. If it is someone else, it needs the authorization of the company to be effective;

3. The labor contract only has the official seal of the employer. The official seal has the highest effect among all seals and can represent the will of the legal person. The official seal means that the organization has approved the contract.

Legal risks of enterprises not signing labor contracts;

1. If the employer fails to conclude a written labor contract with the employee for more than one month and less than one year from the date of employment, it shall pay the employee twice the monthly salary. Therefore, enterprises should pay double wages when dissolving labor relations. If not, employees can apply for labor arbitration;

2. The employee may terminate the labor contract by notifying the employer in writing 30 days in advance. If the contract is not signed, the employee can terminate the relationship at any time without being liable for compensation. As a result, the binding force of enterprises on workers becomes weaker;

3. Failure to sign a contract can lead to the establishment of an open-ended labor contract. If the employer fails to conclude a written labor contract with the employee within one year from the date of employment, it shall be deemed that the employer has concluded an open-ended labor contract with the employee. This is not good for enterprises;

4. The unit cannot dismiss employees on the grounds of unqualified probation. If the employee is proved not to meet the employment conditions during the probation period, the employer may terminate the labor contract. Therefore, if a contract is signed to stipulate the probation period, the enterprise can dismiss employees at any time on the grounds that they do not meet the employment conditions during the probation period without paying economic compensation. If you don't sign a contract, there is no probation period, and you must pay economic compensation for dismissing employees;

5. Failure to sign a contract still cannot exempt employees from the obligation to pay various social security fees. The law stipulates that as long as labor relations exist, enterprises should fulfill all the obligations stipulated in the labor law. If not, workers can complain to the labor inspection department.

To sum up, it is illegal for state organs, institutions, social organizations and workers who have established labor relations with them not to sign labor contracts or pay social security in time. Workers can safeguard their legitimate rights and interests through labor arbitration or prosecution, and employers need to compensate and repay those who have not signed labor contracts and failed to pay social security.

Legal basis:

Article 165 of the Civil Code of People's Republic of China (PRC)

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.