It has submitted a petition against Treasury. Here's what it claims:
Delta Asia Group, parent company of BDA, released a copy of the 19-page petition filed with the Treasury last week by U.S. lawyer Mary Ellen Powers on behalf of Au and the group.
At the end of an 18-month investigation, the Treasury concluded that BDA turned a blind eye to illicit activities but decided to release the funds to Pyongyang to facilitate the stalled six-way denuclearization talks.
"(Releasing the funds) is inconsistent with any claim that the funds were actually the proceeds of illicit activities," Powers said in the petition.
"During a congressional hearing, (U.S. Deputy Assistant Treasury Secretary) Daniel Glaser refused to characterize the funds as 'ill-gotten gains' of illegal activity," she added.
Powers said the Treasury's ruling was simply aimed at sending a signal to the international financial community.
"Glaser admitted in his congressional testimony that (the Treasury) had singled out one small bank and imposed extraordinary sanctions with no warning in order to scare the financial community," she said in the petition.
Powers quoted former senior U.S. State Department official David Asher as saying BDA was just an "easy target" and that the ruling aimed to "kill the chicken to scare the monkey."