At about 1750 Pacific time, the unlicensed pilot of an unregistered Sabre Trike 330 lost control during an unintentional takeoff near Jean. The pilot was killed. The owner of the aircraft said the pilot was going to taxi the aircraft, but inadvertently became airborne. The owner said, after a series of up and down movements, the aircraft stalled, turned, and went straight in. The owner was not aware that the aircraft did not comply with the requirements of FAR 103, which specifies the requirements an aircraft must meet in order to operate as an ultralight vehicle.