Kei Komuro, the husband of former Princess Mako, has been registered as a lawyer in the U.S. state of New York, a local judicial website showed.
Komuro's registration, dated Monday according to the New York State Unified Court System, came after he passed the state's bar examination on his third attempt last July.
His title in a legal firm in New York he has been working for has been changed from law clerk to associate.
Komuro, 31, graduated from New York City's Fordham University School of Law with a Juris Doctor degree in May 2021. He and Emperor Naruhito's 31-year-old niece have been living in the city since late 2021.
They married in October that year amid public unease over the marriage due to a financial dispute involving Komuro's mother and her former fiance.
The 1947 Imperial House Law, which limits heirs to the imperial throne to males with an emperor in the paternal line, requires female royals to give up their status when they marry commoners.