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Press Release

Former Bellevue, Washington resident pleads guilty to securities fraud for defrauding investors and marijuana businesses

For Immediate Release
U.S. Attorney's Office, Western District of Washington
Admits lying on multiple filings and public statements; Agrees to join prosecutors in requesting a ten-year prison term

Seattle – A 42-year-old Las Vegas man, who previously lived in Bellevue, Washington, pleaded guilty today in U.S. District Court in Seattle to securities fraud, announced U.S. Attorney Nick Brown. Justin Costello admits in his plea agreement that he victimized marijuana business owners, private investors and investors who purchased stock in the public market.  Under the terms of the plea agreement, both the prosecutors and the defense will recommend a ten-year prison sentence when Costello is sentenced on April 21, 2023. U.S. District Judge Ricardo S. Martinez is not bound by the recommendation and can impose any sentence allowed by statute.

While Costello pleaded guilty to one count of securities fraud, the plea agreement specifies that the court can take into account all of Costello criminal conduct as relevant conduct for sentencing purposes. Costello not only defrauded investors, he stole from three marijuana business who trusted him for banking services.

As part of his securities fraud scheme, Costello purchased two companies that were trading for pennies on the over-the-counter market and renamed them GRN Holding Corporation and Hempstract Inc.  Costello recruited investors in these companies, allegedly making numerous false statements. Costello told potential private investors that he had an MBA from Harvard, that his personal wealth was significantly larger than it was, and that GRN Funds LLC, a private equity and hedge fund he owned, had over $1 billion in assets under management. None of that is true.

With these falsehoods, Costello convinced various investors across the country to invest in his companies. Costello also had press releases and securities filings made with multiple false representations. Between July 1, 2019, and May 18, 2021, over 7,500 investors purchased and sold GRN Holding Corp. securities while Costello was making, and causing to be made, material misrepresentations concerning GRN Holding Corp. Collectively, these investors lost approximately $25 million. Similarly, with Hempstract Inc., he made false statements and defrauded investors. Between November 2018 and June 2021, 29 private investors lost about $6 million.

Between October 2019, and January 2021, Costello hired an unindicted coconspirator to use Twitter in a pump and dump stock scheme. Costello would acquire the penny stock of a company and then instruct his prolific Twitter user to tweet falsehoods about the company that would drive up the stock price. The coconspirator would tweet about the stock as often as 90 times a day. In one instance Costello didn’t just use Twitter, he also instructed some of his “investors” to purchase stock in the company, driving the share price from a nickel to $2 per share. After driving the share price up, Costello sold the shares for a profit of more than $355,000. The prolific Twitter user was given a share of Costello’s profits from the pump and dump scheme. In all Costello made $625,092 in the pump and dump scheme.

Along with the securities fraud, in 2017 Costello owned and operated a company called Pacific Banking Corp that provided banking services to marijuana businesses in Washington, Colorado, California, Illinois, and Alaska. Costello sent false account statements to the marijuana businesses, so that they were lulled into thinking their money was secure. However, between 2019 and 2021, Costello diverted money from three marijuana business to benefit himself and his other companies. The three marijuana businesses lost about $3.7 million.

Costello was apprehended October 6, 2022, by law enforcement in Southern California. He had fake identification documents, cash and valuables indicating he hoped to flee to Mexico to avoid prosecution.

In the plea agreement Costello agrees to pay at least $35 million in restitution.  He is also forfeiting assets that were seized at the time of his arrest including $60,000 in cash, gold bars, Mexican pesos, two designer watches, and gem encrusted jewelry.

The case was investigated by the FBI. 

money, gold, fake ID

The case is being prosecuted by Assistant United States Attorney Justin Arnold and Michael Dion.

Seized jewelry

Press contact for the U.S. Attorney’s Office is Communications Director Emily Langlie at (206) 553-4110 or

Updated January 18, 2023

Financial Fraud
Securities, Commodities, & Investment Fraud
Press Release Number: 1