Dear fellow union member!
If anyone tells you that our company does not acknowledge this union,
here is what they and we have signed.
Click here for the Japanese original or here for the English translation.
Even without this Japanese Labour Law states this on the Organization of a Labour Union:
".....any employee can organize one freely at any time with the minimum of two members.There is no need to gain consent from the company if a labour union is organized independently and operated democratically by the employees."