The lawyers claimed that the donors he arranged to give up kidneys were fully aware of what they were doing.
But anthropologist and organ trade expert Nancy Scheper-Hughes, who described Israel as a 'pariah' in the organ transplant world, has said in the past that many of the donors were desperately poor immigrants from eastern European countries such as Moldova, Romania and Russia.
They say the recipients are leading healthy lives thanks to Rosenbaum.
The 60-year-old was arrested two years ago following a huge investigation into corruption in New Jersey.
The probe led to 46 arrests, including several rabbis, the New York Daily News reports.
'I am what you call a matchmaker ... I've never had a failure.'
He was nabbed after an FBI informant who was pretending to be a businessman told him he was looking for a new kidney for a sick uncle
Rosenbaum was caught on tape boasting that he had brokered 'quite a lot' of illegal transplants.
He told the informant: 'I am what you call a matchmaker.'
'I bring a guy what I believe, he's suitable for your uncle ... I've never had a failure.'
Prosecutors said he bought the organs from vulnerable people in Israel for as little as $10,000, then sold them here for a minimum of $120,000.
New Jersey's U.S. Attorney Paul Fishman said: 'A black market in human organs is not only a grave threat to public health, it reserves lifesaving treatment for those who can best afford it at the expense of those who cannot. We will not tolerate such an affront to human dignity.'
Caught in a sting: Rosenbaum is handcuffed and arrested in 2009 after a huge probe intro corruption in New Jersey
Rosenbaum faces a maximum five-year prison sentence on each count, plus a fine of up to $250,000. He also agreed to forfeit $420,000 in property that came from the kidney sales.
He is a member of the Orthodox Jewish community in the Borough Park section of Brooklyn, where he had told neighbors he was in the construction business.
Under 1984 federal law, it is illegal for anyone to knowingly buy or sell organs for transplant.
The practice is illegal just about everywhere else in the world, too.
But demand for kidneys far outstrips the supply, with 4,540 people dying in the U.S. last year while waiting for a kidney, according to the United Network for Organ Sharing.
Evil plan: Rosenbaum's home in Brooklyn where the matchmaking was masterminded
As a result, there is a thriving black market for kidneys around the world.
Art Caplan, the director of the Center for Bioethics at the University of Pennsylvania and a co-chairman of a United Nations task force on organ trafficking, said kidneys are the most common of all trafficked organs because they can be harvested from live donors, unlike other organs.
He said Rosenbaum had pleaded guilty to one of the 'most heinous crimes against another human being.'
Mr Caplan said: 'Internationally, about one quarter of all kidneys appear to be trafficked.
'But until this case, it had not been a crime recognized as reaching the United States.