A labor contract is established by agreement between a Worker and an Employer on the basis that the Worker will work by being employed by the Employer and the Employer will pay wages for such work.

If a Worker and an Employer conclude a labor contract, and the Employer has informed the Worker of the rules of employment that provide for reasonable working conditions, the contents of the labor contract are to be based on the working conditions provided by such rules of employment; provided, however, that this does not apply to any portion of the labor contract in which the Worker and the Employer have agreed on working conditions that are different from the contents of the rules of employment, except in cases that fall under Article 12.

A Worker and an Employer may, by agreement, change any working conditions that constitute the contents of a labor contract.

An Employer may not change any of the working conditions that constitute the contents of a labor contract in a manner disadvantageous to a Worker by changing the rules of employment, unless an agreement to do so has been reached with the Worker; provided, however, that this does not apply to the cases set forth in the following Article.

When an Employer changes the working conditions by changing the rules of employment, if the Employer informs the Worker of the changed rules of employment, and if the change to the rules of employment is reasonable in light of the extent of the disadvantage to be incurred by the Worker, the need for changing the working conditions, the appropriateness of the contents of the changed rules of employment, the status of negotiations with a labor union or the like, or any other circumstances pertaining to the change to the rules of employment, the working conditions that constitute the contents of a labor contract are to be in accordance with such changed rules of employment; provided, however, that this does not apply to any portion of the labor contract which the Worker and the Employer have agreed on as being the working conditions that are not to be changed by any change to the rules of employment, except in cases that fall under Article 12.

Procedures for changing the rules of employment are governed by the provisions of Article 89 and Article 90 of the Labor Standards Act (Act No. 49 of 1947).

A labor contract that stipulates any working conditions that do not meet the standards established by the rules of employment is invalid with regard to such portions.In this case, the portions which have become invalid are governed by the standards established by the rules of employment.

If the rules of employment violate any law or regulations or collective agreement, the provisions of Article 7, Article 10 and the preceding Article do not apply to a labor contract with a Worker to whom said law or regulations or collective agreement applies, with regard to said portion in violation.