Learn in the textbookRules for Handling Personal Information — Consent, Third-Party Provision, and Processing
DefinitionThird-party provision (第三者提供) means a business handing personal data it holds to anyone other than the person and the business itself, and in principle it requires the person's prior consent.
ExplanationExceptions that allow provision without consent include cases based on laws and regulations and cases where it is needed to protect someone's life, body or property and getting the person's consent is difficult. Separately, recipients who get data through outsourcing, through business succession in a merger or similar, or through joint use after the person has been notified in advance are not third parties in the first place.
AnalogyIt is like asking a friend before showing someone else a letter they left with you. But when you cannot ask, say during a fire when they cannot be reached, different handling applies.