He has been labelled "dangerous" and a "health risk" to women - an international sperm donor with a goal of getting as many women pregnant as possible.
"Joe Donor", who hasn't revealed his real name, calls himself the "miracle maker" and has a goal of fathering up to 2500 children.
The American arrived in Australia in January.
In an interview with 60 minutes Australia, reporter Liz Hayes criticised his behaviour - questioning his methods and what seemed to be a lack of regard for the health of the women he impregnates.
“You are risking women's lives by your very deliberate actions,” Hayes said. “You are not helping anyone. You liken yourself to some doctor on call for desperate women.”
Mr Donor has fathered children across the United States, South America and Australia.
He estimates he has attempted more than 800 inseminations, which have resulted in more than 100 children.
“I’m basically only having sex to get women pregnant. I’m not chasing rainbows or fantasies,” he told the reporter.
Mr Donor offers his sperm to women for artificial use at no cost other than reimbursement of his expenses.
He told 60 minutes that natural insemination and unprotected sexual intercourse is a more "effective" way of getting pregnant.
He says half of his clients choose the natural method.
Family and fertility expert and lawyer Stephen Page said Mr Donor is putting vulnerable women and their potential children at serious risk.
“He's really playing the role of God, and he shouldn't be playing the role of God towards desperate women and their kids,” Mr Page told the programme.
“I just think he's mad, and dangerous, and these women shouldn't be going anywhere near him.”
But what has caused a lot of controversy is his dismissive attitude towards women’s health and proper medical checks.
“Some people - they want to do a background check, a drug test. And I’m like, 'You know you’re not giving me the keys to the nuclear missiles – we’re just making a baby',” Mr Donor said.
He said he believes that medical checks and screenings for sexually transmitted diseases are part of a conspiracy by IVF clinics to make money.
Mr Page said even though he gets checked once a year, it’s simply not enough at the rate at which he has unprotected sex.
“Sooner or later, the odds are he may well have HIV and transmits that to someone else. What a disaster,” he says.
The "real risk", Mr Donor argued on the programme, "is that a woman will die a spinster without a child.”
Hayes fired back: “The real risk is that you’re totally deluded."