A settlement in principle for Florida businessman Barry Honig now appears to be off the table, according to a filing on Tuesday in the case that was signed by all parties.
The Securities and Exchange Commission brought charges for what it called "classic pump-and-dump schemes" in September.
The SEC filed for an extension of time on April 26 for a planned settlement.
"Defendant Honig and the Commission staff reached an agreement in principle to settle the Commission's claims for liability," the April motion said.
Now, the situation appears to have changed.
"The parties do not believe there is a possibility of prompt settlement of this case, although the Commission has noted its willingness to discuss settlement with any Defendant," the Tuesday filing said.
Two attorneys for Honig declined to comment. His other three attorneys were not immediately available.
No details about the potential settlement were released. The SEC declined to comment.
"Honig was the primary strategist, calling upon other Defendants to, among other things, acquire or sell stock, arrange for the issuance of shares, negotiate transactions, and/or engage in promotional activity" in the $27 million schemes, according to the SEC's amended complaint, filed in March.
The SEC charged 19 others along with Honig. The SEC already settled in full or in part with nine defendants, including Miami biotech billionaire Phillip Frost, according to the April extension filing.
Honig was once the largest shareholder of Riot Blockchain, the cryptocurrency company whose stock skyrocketed after it changed its name from Bioptix. He was charged by the SEC along with John O'Rourke, the former CEO of Riot Blockchain, who left Riot in the wake of the charges. O'Rourke remains a defendant in the case.
The SEC case is unrelated to Riot Blockchain.
A CNBC investigation in February 2018 found a number of red flags at Riot Blockchain, including annual meetings that were postponed at the last minute, sales of stock by company insiders soon after the company's name change, dilutive share issuances on favorable terms to large investors, confusing SEC filings and evidence that a major shareholder was selling shares while everyone else was buying.
"We have made significant inroads in building a diversified portfolio of investments and to begin securing digital assets," O'Rourke said in a letter to shareholders the day the CNBC investigation aired.
As bitcoin's price hit record highs in late December 2017, Riot was making news on a daily basis. The company's stock shot from $8 a share to more than $40 as investors chased the craze of all things crypto.