Mamoru Shigemitsu signed Japan's surrender document at 9:04 a.m. Tokyo time.
Shigemitsu was the first person to sign the Instrument of Surrender during the ceremony aboard the USS Missouri. He signed on behalf of the emperor and the Japanese government. General Yoshijiro Umezu followed at approximately 9:06 a.m., signing for Japan's Imperial General Headquarters.
The ceremony then moved to the Allied representatives. Douglas MacArthur signed at approximately 9:08 a.m., followed by Chester Nimitz and representatives of the other Allied powers. The proceedings ended at about 9:25 a.m., when the surrender became officially effective.
The time is easy to confuse with other important wartime times. Hiroshima's atomic bombing occurred at 8:15 a.m. on August 6, while Hirohito's surrender broadcast began at noon on August 15. The 9:04 a.m. time specifically identifies Shigemitsu's first signature at the formal ceremony.