When Imam Bukhari brings a muʿallaq hadith with sigha al-jazm, such as So-and-so said or So-and-so narrated, it indicates that its chain was established as authentic according to him by a sound route - Muhammad Abd al-Rauf al-Manawi

Al-Yawaqit wa al-Durar cover - Muhammad Abd al-Rauf al-Manawi
When Imam Bukhari brings a muʿallaq hadith with sigha al-jazm - Muhammad Abd al-Rauf al-Manawi