Passer-by data is personal data captured about people who are not directly using a device or service. A smart-glasses camera, for example, may record nearby people’s faces or presence even though they did not choose to use the glasses.
This matters because recording can create privacy and data-protection obligations beyond the wearer’s own account. In real deployments, manufacturers and service providers may need to consider transparency, a lawful basis for processing, data minimization, retention limits, and privacy safeguards built into the product. Visible recording indicators and limits on collection can help reduce risk, but they do not automatically resolve every legal issue.