Sherman was born into a Jewish family in Toronto to Herbert Dick “Hyman” Sherman (1906–1952), a business partner for a zipper company, and Sara “Sarah” Sherman (née Winter; 1910–1971), an occupational therapist after her husband’s death. His grandparents from both sides had fled persecution of Jews in Russia and Poland. His father died from a heart attack when Bernard was 10. He won a national physics contest while attending the Forest Hill Collegiate Institute and graduated with top marks. In 1958, he entered the University of Toronto’s engineering science program at age 16, believed to be the youngest to do so until Madeline Zhang in 2016 who entered at the age of 14. He wrote later that he chose that program specifically because it was reputedly the university’s hardest. The same year, he signed up for a Canadian Army organized student militia.

He graduated from the University of Toronto with the highest honours in his class, and received the university’s Governor General’s Award for his thesis. He enrolled at the Massachusetts Institute of Technology to begin doctoral studies in engineering. In 1967, he completed a PhD in astrophysics from MIT.

In 1967, after completing his PhD, Sherman purchased the Empire Group of Companies from the executor of the estate of his aunt and uncle, Beverley and Louis Lloyd Winter, as both had died 17 days apart in November 1965, leaving four orphaned young children: Paul Timothy, Jeffrey Andrew, Kerry Joel Dexter, and Dana Charles. Empire had been the first to secure the compulsory rights to manufacture Hoffmann-La Roche’s Valium (diazepam) in Canada, and was one of Canada’s largest manufacturers of Pfizer’s Vibramycin (doxycycline), Upjohn Company’s Orinase (tolbutamide), and the dietary sweetener saccharin. The estate allowed Sherman to buy a majority stake in the company and run it only on the condition that the four Winter children be allowed to work for the company when they reached 21, with the option to buy 5 percent stakes in the company two years later, with 15-year royalties on four of its patented products. The agreement would be voided if Sherman sold Empire.

That voiding happened in 1969. Sherman worked out a deal to swap shares with Empire’s largest customer that put it in control of the company. In 1970 he invested in New York’s Barr Laboratories with US-based partners, became its largest shareholder and served as Barr’s president. He would eventually control a third of Barr’s stock. Barr won the first rights to manufacture generic versions of Eli Lilly’s Prozac. Today, Barr Laboratories’ is a part of Teva Pharmaceutical Industries, the world’s largest generic drug maker, following Teva’s acquisition of Barr Pharmaceuticals in 2008.

Sherman married Honey Reich in 1971, a fellow University of Toronto graduate born in Austria, to Polish Jewish, Holocaust survivors. They had four children, a son, Jonathon, and three daughters, Lauren, Alexandra and Kaelen.

In January 1972, Sherman and Ulster Limited sold Empire Laboratories to the Quebec-based Canadian operations of publicly traded International Chemical and Nuclear (ICN) of California, for 57,000 shares (Valeant Pharmaceuticals). This transaction voided his arrangement with the Winter estate. A year later, Sherman started Apotex with a few former Empire Laboratories’ personnel; it was incorporated in 1974. This privately owned and Sherman-controlled company claims to be Canada’s largest Canadian-owned pharmaceutical manufacturer. Sherman also became involved in Nutraceutical manufacturing and other businesses, founding NION (National Institute of Nutrition) with Richard Kashenberg. He later sold the company to Schiff and continued on to Apotex.

Sherman was also known for the vigor of his lobbying efforts. When Brian Mulroney’s government passed a law in 1993 that extended patent protection for brand-name drug makers, Sherman complained that it would be destructive to smaller generic drugmakers and began supporting Jean Chrétien and the Liberal Party, who had promised to review the law if they took power. He also donated millions of dollars to U of T for a research center, contributions he withdrew when the letters they wrote to the government opposing the new regulations did not result in those regulations being withdrawn.

A yacht-chartering company he put money into turned out to be a fraud that had never bought any yachts. Later he bought a majority stake in a company that sold a nutritional supplement marketed by American Kevin Trudeau. In 1996, when U.S. regulators began investigating the fraud claims that have since led to Trudeau’s imprisonment, Sherman sold half his stake to the Apotex Foundation.

In 1996, after the Shermans’ North York home was completed following five years of construction, the couple was dissatisfied with the work done on it. In particular, they claimed that the garage, a structure with a tennis court on top and a basement lap pool and hot tub, was faulty; Barry called it a “disaster”. He and his wife filed 12 separate suits against all the contractors; ultimately they would recover almost the entire estimated $2.3 million cost of building the house through favourable judgements.

In 2006, still unsatisfied, Sherman supported the campaign of Joe Volpe to become Liberal leader. He and other Apotex executives gave $108,000 to Volpe’s campaign, all giving the legal maximum of $5,400. This caused some controversy when some of those donations were found to have come from minor children of the executives, although ultimately Elections Canada ruled that no laws were broken.

For 15 years Sherman also partnered with Frank D’Angelo, a fruit-juice maker who was trying to branch out into other businesses. The two produced the Cheetah Power Surge energy drink and started Steelback Brewery; when D’Angelo Brands went bankrupt in 2007, Sherman lost CAN$100 million. He put his son in charge of the company, and continued backing D’Angelo’s next venture, filmmaking, even after D’Angelo was arrested on sexual assault and obstruction of justice charges, later dropped, in 2009. Sherman’s money financed all eight films D’Angelo made through 2013.

In 2011, the Winter children (his cousins) sued Sherman alleging he never paid royalties and equity in Apotex, contending Sherman had used the proceeds from the 1972 sale of their late father’s business Empire to buy Apotex in 1973. The cousins sought a 20 percent interest in Apotex or damages of $1 billion. Sherman responded by withdrawing millions of dollars in financial assistance to his cousins. The cousins’ contended that Sherman “had offered the financial assistance in the first place in order to make the cousins dependent on him, and to keep them from learning about their rights to the business”, an allegation Sherman denied. In September 2017, an Ontario Superior Court justice ruled against the cousins, saying the case was “wishful thinking, and beyond fanciful.” At the time of the judgement, a lawyer for the cousins said they would appeal, though no appeal occurred, and Sherman died a few months later.

At the time of his death, Sherman, legally registered as a lobbyist, was under investigation because of a fundraiser he had held for Justin Trudeau in April 2015, allegedly contrary to Canada’s lobbying rules. Sherman filed a lawsuit in May 2016, attempting to quash the investigation before it was finished, a legally unprecedented move in Canadian history. “There is basis to conclude that Mr. Sherman is in breach of … the Lobbyists’ Code of Conduct as a consequence of his involvement in the organization of a fundraising event for the (Liberal Party),” according to Phil McIntosh, director of investigations at the Office of the Lobby Commissioner. If that had been proven, Sherman would have been banned from lobbying for five years.

By 2016, Apotex employed over 10,000 people as one of Canada’s largest drug manufacturers, with over 260 products selling in over 115 countries. Revenues were about $1.5 billion annually.

In 2017, the Shermans decided to sell their longtime home on Old Colony Road in North York and move to a new one they were building in Forest Hill, closer to downtown Toronto, where they would have as neighbours many of the people they socialized and did business with. Honey, who according to Frank D’Angelo had initiated the move, had purchased a corner lot in November 2016; the Shermans planned to demolish the existing house on the site. Plans for a replacement on file with the city called for a 16,000-square-foot (1,500 m) house with features such as a central swimming pool with 41-foot (12 m) retractable skylight and living quarters for staff. The 15 variances required, including the house’s 47.6-metre (156 ft) depth, more than twice that allowed in the city’s zoning, and a car stacker in the garage, were approved in June 2017.

In January 2018, the Toronto Star published an exclusive report based on anonymous sources from the family’s investigation team who said that the deaths were murders: the couple was strangled by belts after their hands were tied. These investigators had not yet gained access to the Sherman home. “People providing information for this story are not identified as they were not authorized to discuss the case,” according to the Star. When contacted by a reporter, a Toronto Police spokesman reiterated the position that they were treating the deaths as “suspicious”. On January 26, Toronto Police advised the news media that their investigation concluded that the couple had been killed in a targeted attack. At the time, they would not discuss any possible suspects, but planned to interview everyone who had access to the home prior to the deaths via the lockbox that was previously installed by the real estate agent. The police investigation has encountered resistance at Apotex headquarters, with a police spokesman saying “Legal complexities in some executions have been challenging given the litigious nature of Barry Sherman’s businesses, in particular the search and seizure of electronics in Barry Sherman’s workspace at Apotex”.

The police investigation was still continuing in September 2018 when detectives obtained seven search warrants in addition to the 21 previously obtained. Detective Dennis Yim told a court that “investigators are methodically reviewing material and pursuing different investigative avenues”.

By October 2018, police had obtained 37 warrants related to the investigation.

On April 25, 2019, the Toronto Police said they had a “working theory” of the case, and an “idea of what happened.”

In June 2019, persons close to the Shermans said Barry had planned to give to charity or invest much of his fortune. Trustees for the Sherman family fought to keep details of the estate secret. In Canada, court documents and related proceedings—including files that deal with an estate after death—are public. An Ontario Superior Court judge applied a “protective order” to the file, but media in Canada appealed and won. The family appealed to the Supreme Court.