Is the factory building leased in a different place in the same city as the company? If you are in the same city, it is legal for you to do so. Only when they are not in the same administrative division will they be investigated and punished by the tax bureau for alleged tax evasion. However, you have to go through the filing procedures for production in different places at the industrial and commercial bureau where the company is registered, because your workshop is not a business place after all.