Tehran said it had decoded hard drives and databases on the RQ-170 Sentinel - an announcement that indicates Russia and China could access to the top-secret technology.
The drone went down in December in eastern Iran and was recovered by Iran almost completely intact.
General Amir Ali Hajizadeh, head of the Revolutionary Guards aerospace division, said engineers were in the final stages of decoding data from the Sentinel aircraft, Mehr news agency reported.
'I am giving you four codes so the Americans understand just how far we have gone in penetrating the drone's secrets,'
"In October 2010, the aircraft was sent to California for some technical issues,it was taken to Kandahar (in Afghanistan) in November 2010, when a series of technical problems still prevailed,in December 2010, it was sent to an airport near Los Angeles for repair of its equipment and sensors, and flight tests. The drone was then sent back to Kandahar,'
Hajizadeh told state television that the captured surveillance drone is a "national asset" for Iran and that he could not reveal full technical details.
The drone, equipped with stealth technology that makes it virtually undetectable on radar can carry advanced sensors capable of sending back a trove of imagery and electronic intercepts.
Despite repeated warnings from the Pentagon, Barack Obama rejected three plans to recover or destroy the US drone that was intercepted over Iranian territory.