To define confidential documents simply, they are "documents that contain information of paramount importance to a company, and whose confidentiality is absolutely essential."
When we hear the term "confidentiality," we tend to imagine information that we don't want other companies to know, but the scope is not always limited to that. For example, management strategies that are not yet made public should be kept confidential from general employees until the time comes, and it would be problematic if personnel-related data could be freely accessed by employees outside the HR department. Confidentiality applies to both external and internal matters. Although there are no codified regulations in laws and regulations, documents are generally classified into three categories based on their importance: "top secret documents," "confidential documents," and "confidential documents for external use."
Furthermore, documents other than those created in-house, such as customer lists submitted by business partners, information on joint research, and specifications and drawings not yet made public, as well as digital data not stored in paper form, will be treated as confidential documents depending on their content.