Quadriga Fintech Solutions was the owner and operator of QuadrigaCX. QuadrigaCX was believed to be Canada's largest cryptocurrency exchange at the time of its collapse in 2019, with the exchange ceasing operations and the company filing for bankruptcy with C$215.7 million in liabilities and about C$28 million in assets.

The company's CEO and founder, Gerald William Cotten, died in December 2018 after traveling to India. Up to C$250 million (US$190 million) in cryptocurrency owed to 115,000 customers was missing or could not be accessed because only Cotten held the password to off-line cold wallets.

Quadriga likely never invested the funds entrusted to it, according to Chainalysis, a cryptocurrency tracking firm. Either the funds were never received or quickly went missing. "What Quadriga really did with the money that customers gave it to buy Bitcoin remains a mystery," according to Chainalysis.

Gerald Cotten (born 11 May 1988) lived in Belleville, Ontario, before attending the Schulich School of Business at York University in Toronto. He graduated from York with a bachelor of business administration in 2010.

Cotten was already involved in Ponzi schemes as a teenager, using the online handle Sceptre on the online forum TalkGold. There, Cotten would promote HYIPs (high-yield investment programs) that "promised very high returns but were unregulated and anonymous, disclosing little or no details about the investment or who was behind it", while transactions were anonymous and hidden using digital currency. Cotten secretly cooperated with Michael Patryn on these Ponzi schemes. Cotten also sold a "proxy service that would reroute a user's internet connection so that their IP address would be hidden".

Cotten learned about Bitcoin in Toronto and travelled to Vancouver, British Columbia, where he founded Quadriga in November 2013 with Michael Patryn. Cotten and Patryn were previously involved in online Ponzi schemes, but whereas Patryn had caught the attention of authorities, Cotten's involvement had not been discovered yet, so Cotten's sterling reputation enabled him to be the public face of Quadriga.

Quadriga started by doing only local trades. Their online exchange launched after the first month. In January 2014 they installed the second Bitcoin ATM in Vancouver. In 2014, C$7.4 million worth of bitcoin were exchanged on Quadriga. In a 2014 interview, founder Gerald Cotten explained that the company stored customer funds on paper wallets in safe deposit boxes: "So we just send money to them, we don't need to go back to the bank every time we want to put money into it. We just send money from our Bitcoin app directly to those paper wallets, and keep it safe that way."

In 2016, Cotten became the sole director of Quadriga when all the other directors resigned. Other than a few contractors, it had no employees, offices, or bank accounts thereafter.

Quadriga co-founder Michael Patryn was identified by The Globe and Mail as Omar Dhanani, who was convicted on identity theft charges in the U.S. and served 18 months in Federal prison. Dhanani also had pleaded guilty to burglary and grand theft charges and had been deported to Canada. Bloomberg also identified Patryn as Dhanani, showing that he had officially changed his name from Omar Dhanani to Omar Patryn in British Columbia in March 2003 and changed it again to Michael Patryn in October 2008.

According to Jennifer Robertson, Cotten's widow, he died on 9 December 2018 while travelling in India. She had accompanied him to a hospital in Jaipur the previous day and he was diagnosed with septic shock, perforation, peritonitis, and intestinal obstruction. On the 9th, he allegedly died after episodes of cardiac arrest. On 10 December, a death certificate was issued by the local municipality as well as a "no objection certificate" from the police to return the body to Nova Scotia.

Robertson filed an affidavit on behalf of the company which included a "Statement of Death" for Cotten, filed in Halifax, Nova Scotia, on 12 December 2018. It also stated that Quadriga has 363,000 registered users and a sum of C$250 million is owed to 115,000 affected users.

Cotten's will was signed 27 November 2018, twelve days before he allegedly died. It left Robertson the entire C$9.6-million estate and named her as the trustee. The estate includes an airplane, a sailboat, a 2017 Lexus, and real estate in Nova Scotia and Kelowna, British Columbia. A C$100,000 trust fund was made to provide lifelong care for Cotten's two chihuahuas in case of Robertson's death.