Discussion paper presenting a proposal for technical requirements for an Automated Driving System marker lamp to improve social acceptance and facilitate traffic management and enforcement. The proposal addresses installation position (mandatory front and rear, optional side), visibility angle equivalent to direction-indicators, luminous intensity variation (continuous illumination without flashing, except nighttime dimming), combined use with direction-indicators (ADS marker lamp turned off when direction-indicator operates on same side), and applicable vehicle categories (M, N, L₆, L₇, and O when towed by automated driving vehicle). Survey results from Japan, UK, US, and Germany indicate approximately 70% of respondents support distinguishing automated from manual driving modes externally.