EU’s Largest Bitcoin Miner Northern Data Sold to Tether-run Companies, But There’s a Twist

Key Takeaways

• The November sale of Peak Mining, the Bitcoin mining subsidiary of Northern Data, has raised concerns.
• The sale was made to three companies, two of which are directly owned by two of Tether’s founders.
• This was the second attempt, following an earlier deal for the Peak Mining sale that had collapsed.

When Northern Data sold its Bitcoin mining subsidiary, Peak Mining, in November, the transaction appeared straightforward.

A strategic exit from mining as the company doubled down on artificial intelligence (AI) and high-performance computing (HPC).

Weeks later, the deal is drawing renewed attention.

A new investigative report has raised questions about who ultimately bought the asset—and whether the sale created a conflict of interest involving Tether’s top executives.

At the center of the controversy is the ownership structure of the buyers, several of whom are now reported to be directly linked to Tether’s leadership, at a time when Tether itself holds a controlling stake in Northern Data.

Who Bought Peak Mining?

Northern Data sold Peak Mining for a total consideration of up to $200 million to a group of three companies:

• Highland Group Mining Inc., registered in the British Virgin Islands.
• Appalachian Energy LLC, based in Delaware.
• 2750418 Alberta ULC, incorporated in Canada.

Corporate filings reviewed by the Financial Times show that at least two of these entities are controlled by Giancarlo Devasini, Tether’s co-founder and chairman, and Paolo Ardoino, Tether’s chief executive.

Devasini and Ardoino are listed as directors or controlling figures across the ownership structures, while details around Appalachian Energy’s control remain less clear.

The connections matter because Tether already holds roughly 54% of Northern Data, making it the company’s controlling shareholder.

Tether has also provided Northern Data with a €610 million loan, further tightening the financial relationship between the two firms.

In that context, the sale of a major asset to companies tied to Tether’s leadership shifts the transaction into the realm of related-party dealings—something that was not explicitly disclosed when the deal was announced.

The Twist: Timing, Structure, and Disclosure

Northern Data trades on a secondary German market with lighter disclosure requirements than a main exchange listing.

As a result, the company was not required to publicly identify the buyers or flag the transaction as related-party at the time of the sale.

The identities of the acquiring entities only became clear through filings in the British Virgin Islands, the United States, and Canada, weeks after the transaction closed.

The timing has also raised eyebrows.

The sale of Peak Mining was finalized just days before video platform Rumble, in which Tether holds a substantial stake, announced a $767 million acquisition of Northern Data.

While there is no public evidence linking the two deals, the proximity has fueled questions about strategic coordination.

Complicating matters further, this was not the first attempt to sell Peak Mining.

In August, Northern Data had entered a non-binding agreement to sell the unit to Elektron Energy, another company reportedly controlled by Devasini, for $235 million.

That deal collapsed amid whistleblower allegations , and the finalized sale ultimately came at a lower valuation.

A Strategic Exit—or Something More?

From Northern Data’s perspective, the sale fits with its stated goal of exiting Bitcoin mining to focus on AI and data-center infrastructure.

Mining has become a less predictable business amid volatile energy prices and regulatory pressure in Europe, while demand for AI compute has surged.

Still, the ownership links between the seller and buyers introduce governance questions that are difficult to ignore.

Neither Northern Data nor Tether has publicly alleged wrongdoing, and there is no indication that the transaction violated existing regulations.

For now, the sale stands.