December 27, 2023 Administrative Guidance to SoftBank Corp. on Appropriate Responses to Telecommunications Incident

Today, the Ministry of Internal Affairs and Communications (MIC) issued guidance in writing to SoftBank Corp. (headed by MIYAGAWA Junichi, Representative Director, President and CEO, corporate No. 9010401052465, headquartered in Minato-ku, Tokyo) regarding a large-scale telecommunications incident that occurred from Saturday, November 18 through Sunday, November 19, 2023, and again on Monday, November 20, 2023. The guidance strictly cautions against any recurrence of a similar incident and instructs the company to ensure the implementation of various measures from a recurrence prevention perspective.

1. Background

From Saturday, November 18 through Sunday, November 19, 2023, and again on Monday, November 20, 2023, an incident occurred in the fixed telephone service provided by SoftBank Corp., where the provision of a portion of voice transmission services handling emergency calls was halted. In relation to this, on Monday, December 18, 2023, MIC received a report of a significant incident (see Attachment 1 for a summary) from the company, pursuant to Article 28, Paragraph 1 of the Telecommunications Business Act (Act No. 86 of 1984).
The incident caused up to 214,000 users to be unable to use voice transmission services, including emergency calls, for a total of 17 hours and 38 minutes.
Fixed-line telephone service is an important infrastructure for people’s lives. The occurrence of such a serious incident would be detrimental to the interests of users and have a serious impact on social and economic activities. Therefore, MIC issued a strict warning to prevent similar incidents from occurring and provided written guidance to prevent recurrence.

2. Guidance details

Contents of guidance for SoftBank Corporation: Attachment 2.

*The published materials are in Japanese only.