John Rosenthal, a self-styled accountant to the financial stars of Toronto, has been forced into bankruptcy by his estranged wife, owing millions to former clients.
For decades, Rosenthal, 75, was everybody’s “best friend,” holidaying with clients and living the high life. Then, in a spectacular downfall he was accused in court actions of stealing millions in a Ponzi scheme.
Those claims are the subject of more than a dozen court actions, many still a long way from resolution.
Meanwhile, Rosenthal is bankrupt, owing $18,764,799; he lists zero assets on his bankruptcy form.
As detailed in a Toronto Star series, Rosenthal was a chartered professional accountant with a flair for nice things, and a desire to be entrepreneurial, to do more than just keep the books of the wealthy. He had a stable of blue-chip Toronto clients. One of them, Toronto lawyer Peter Israel, often vacationed with Rosenthal and counted him as one of his closest pals. Israel has mused that his accountant friend simply “got in over his head.”
The Star was unable to reach Rosenthal. He did not reply to the Star’s requests for an interview for the original series.
In allegations filed in court and with Ontario’s accountant regulator, Rosenthal is said to have masterminded a real estate investment scheme where he promised his clients high returns. In reality, as clients learned, there was no investment scheme. Investments from one client would help Rosenthal make monthly payments to earlier clients. When the new investments dried up, clients found their cheques were bouncing — a classic indication of a Ponzi scheme.
Some of the allegations are still before court, in others a judge has found Rosenthal in default. He has not filed a defense in these cases. Fifteen lawsuits have been filed, alleging losses of $13 million.
Ontario’s accountant regulator has stripped Rosenthal of his license, finding that he had committed professional misconduct by converting clients money for his own use. He was hit with hefty fines.
Chartered Professional Accountants of Ontario is listed as a creditor, stating that Rosenthal has not paid $251,244 in fines levied against him for “misconduct.”
Former clients say Rosenthal was a whiz at tax advice, helping them structure their finances in the best possible way. Many of the people he advised were multimillionaires. Rosenthal was not, though he was married into the wealthy Lipson family of McGregor Socks fame. His wife — they are listed as separated on the documents — has a claim for $1.9 million relating to money she advanced Rosenthal and his partner Mark Zaretsky, an accountant who has also been stripped of his licence.
Zaretsky declared bankruptcy in September, 2025, owing a similar amount — $17,961,468. A comparison of the two bankruptcy documents reveals they have most of the same creditors, all former clients. There are a few differences, related to their own personal loans, credit card balances or income tax listed as payable.
The major distinction between the two bankruptcies is that Zaretsky assigned himself into bankruptcy. Rosenthal did not.
Instead, his estranged wife, Marcia Lipson, went to Superior Court to get a “bankruptcy order” which forced Rosenthal into bankruptcy. “He has failed to pay his obligations to the applicant and other creditors,” the judge wrote in the order.
Earlier this year, Lipson went to court and obtained a “no contact” order from a Superior Court justice, who wrote in his ruling that he was ordering Rosenthal to stay away from Lipson, noting that she fears for her safety and has been receiving a “barrage” of emails and text messages from Rosenthal demanding money.
In one email referenced by the judge, Rosenthal wrote: “Do you want for me to just perish and die.”
Rosenthal had for a decade been splitting time between a North Toronto home he lived in with Lipson, and a home in Arizona. He was a gourmet cook, loved first-class travel and had a lot of ideas — selling Canadian lobsters to China was one of the more outrageous schemes, which ended in disaster when the lobsters were caught in red tape on a dock in China and they spoiled.
In emails to some of his former clients in the last year, he has apologized for breaching their trust, telling one his wife was divorcing him, his children no longer speak to him and the entire situation has “created a terrible toll on me” for which he accepts “all the blame.”
Some clients think he has money hidden in offshore bank accounts, but Rosenthal has responded by email saying to them that he has “no money, hidden or in a bank.”
Those same clients have emails leading up to Rosenthal’s stunning fall, where he provides a cascade of reasons why he cannot give them their money back. Among them, that he and his firm were hit by a “cyber attack,” that he was the victim of a “major wire fraud” and that he was “sick like a dog.”
In a brief interview on the doorstep of his home this year, Zaretsky said he was “retired and moving on to a new part of my life.”
The Star has reported that several investors made complaints to police, but were told both that the case is too hard to prove, and that prosecutors are reluctant to take on a prosecution unless it is a “sure thing.”
