1. Without seal, the contract is invalid. The main purpose of the riding seal is to avoid changing the contents of the contract because of changing the inside page of the contract, which has no effect on the effectiveness. Unsigned contract pages may be forged. In the event of a dispute, the contract cited by one party will not be recognized by the other party.

2. Legal basis: Article 465 of the Civil Code of People's Republic of China (PRC).

Contracts established according to law are protected by law.

A legally established contract is legally binding only on the parties, except as otherwise provided by law.

Article 466

If the parties have disputes over the understanding of the terms of the contract, the meaning of the disputed terms shall be determined in accordance with the provisions of the first paragraph of Article 142 of this Law.

Where a contract text is concluded in two or more languages, and the agreement is equally authentic, the words used in each text shall have the same meaning. If the words and expressions used in each text are inconsistent, they shall be interpreted according to the relevant terms, nature, purpose and principle of good faith of the contract.

Second, how to deal with one party's breach of contract after signing the contract?

After the signing of this contract, one party has the following breach of contract:

1. Where the other party is required to continue to perform the contract, the observant party has the right to require the breaching party to continue to perform the obligations agreed in the original contract;

2. Ask the other party to pay the liquidated damages, and the breaching party shall pay the liquidated damages regardless of whether there is any damage;

3. Ask the other party to compensate for the loss. If one party fails to perform its contractual obligations or fails to perform its contractual obligations, causing losses to the other party, the amount of compensation shall be equivalent to the losses caused by the breach of the contract.