The US Federal Bureau of Investigation said on Wednesday it did not own the rights to the technical method a contractor used to open an Apple iPhone used by one of the San Bernardino shooters, and therefore could not submit details of the mechanism for an interagency government review.
Amy S. Hess, the FBI's executive assistant director for science and technology, said in a statement that when it hired an outside party to unlock the phone, the agency did not purchase the rights to the technique.
As a result, Hess said, the FBI does not "have enough technical information about any vulnerability" in the iPhone to submit for the interagency review.
If an interagency review, conducted in secret, had been initiated, it would have decided whether the vulnerability could be disclosed to government agencies or the private sector.
The iPhone in question was owned by the San Bernardino County Health Department and assigned to employee Syed Farook, who, with his wife Tashfeen Malik, killed 14 people and wounded 22 during an attack on his co-workers last December.
While officials have not identified the contractor who provided the technique for opening the shooter's phone, a law enforcement official said that the FBI can re-use the unlocking mechanism on other phones, provided it works on those phones.
Hess said the FBI usually does not comment on vulnerabilities found in products, but the agency decided to make a statement because of the "extraordinary nature of this particular case, the intense public interest in it, and the fact that the FBI already has disclosed publicly the existence of the method".
Hess' statement confirmed information from US government sources on Tuesday that the FBI had provisionally decided not to share the iPhone unlocking mechanism because the agency did not own it.