The man who invented the cryptographic mechanism Bitcoin is built on has made his largest public financial statement about the network’s future — not by mining coins or writing papers, but by becoming the dominant private backer of one of Europe’s leading Bitcoin treasury companies.

Adam Back — the British cryptographer who created Hashcash in 1997, the proof-of-work system Satoshi Nakamoto cited by name in the Bitcoin whitepaper and used as the foundation for Bitcoin’s mining algorithm — has committed capital across multiple rounds of Capital B (Euronext Growth Paris: ALCPB; OTC: CPTLF), the Paris-listed firm that styles itself Europe’s first publicly traded Bitcoin Treasury Company. Capital B announced Monday via regulatory filing that it completed a €28.7 million (approximately $33.1 million) private placement and deployed the proceeds to purchase 376 Bitcoin (BTC) for approximately €25.3 million (approximately $29.2 million) — the company’s single largest acquisition in roughly twelve months — bringing its total strategic holdings to 3,521 BTC.

Back’s stake on an ordinary share basis now stands at approximately 17.77%. If the warrants attached to his most recent placement alone are fully exercised, Capital B would receive an additional €49.4 million (approximately $57 million) — enough, at current bitcoin prices near $77,500 per coin, to purchase several hundred more coins. That is not a completed transaction. It is a pipeline.

What the $33M Raise Actually Consisted Of

The financing the company disclosed Monday aggregates two distinct capital operations completed in the days prior, plus a small at-the-market tranche.

The larger instrument was a €21 million (approximately $24.2 million) targeted institutional placement announced August 28, priced at €0.58 per unit and structured as “ABSA” — the French market acronym for shares with attached subscription warrants. Participants included Blockstream co-founder Adam Back and French asset manager TOBAM, which has backed Capital B since the company’s earliest capital raises. Maxim Group LLC served as sole placement agent.

A separate €7.6 million (approximately $8.8 million) placement announced September 2 was subscribed entirely by Back. That tranche also carried the same unit structure: one share at €0.58 (approximately $0.67) plus four five-year warrants at strike prices of €0.75 ($0.87), €0.75 ($0.87), €0.98 ($1.13), and €1.27 ($1.47). A smaller €1.44 million (approximately $1.66 million) at-the-market tranche through TOBAM’s existing ATM program brought the combined raise to approximately €30.1 million (approximately $34.7 million) gross — or €28.7 million (approximately $33.1 million) on a rounded net basis after expenses.

The acquisition itself was executed at an average price of €67,182 (approximately $77,500) per coin — meaningfully below the company’s long-run average acquisition cost of €87,878 (approximately $101,400) per coin — through Swissquote Bank Europe, a Luxembourg-registered virtual asset service provider, with custody secured by Swiss infrastructure firm Taurus.

How the Machine Works

Capital B’s strategy is a European adaptation of the financial architecture that MicroStrategy’s Michael Saylor pioneered beginning in August 2020 and later systematized under the company’s renamed entity, Strategy, which now holds over 800,000 BTC per Bitcoin Treasuries global rankings. The playbook: raise capital through share issuances and attached warrants, convert the proceeds into Bitcoin, and measure performance not in earnings per share but in Bitcoin per fully diluted share — a metric Capital B calls “BTC Yield.”

In Capital B’s case, the specific instrument is the ABSA (action avec bons de souscription d’actions), a standard French capital-markets structure that bundles newly issued ordinary shares with subscription warrants. Each warrant gives the holder the right to subscribe for new shares at a fixed strike price within a defined window — in Monday’s transaction, within five years. The three-tier strike structure (€0.75 / $0.87, €0.98 / $1.13, and €1.27 / $1.47) is calibrated to Capital B’s target stock price trajectory: if the share price reaches those levels, warrant holders exercise and the company receives additional cash, which it then deploys into more Bitcoin.

The BTC Yield metric stood at 2.17% year-to-date as of Monday’s filing, representing a gain of 61.3 BTC — measures how much the Bitcoin-per-diluted-share ratio has grown since January 1. A positive BTC Yield means the company has grown its Bitcoin exposure per share faster than it has diluted shareholders through new issuances. That is the intended proof of the model’s value-creation claim.

Monday’s purchase added 376 BTC at below-average cost, which modestly reduces the blended per-coin cost across the treasury — what the company calls “accretive” to its strategy. This is a real though narrow benefit: buying at €67,182 when the portfolio average is €87,878 pulls the mean down, theoretically improving per-share Bitcoin value even as the total headcount of shares outstanding grows.

The Warrant Pipeline Back Controls

The strategic significance of Back’s participation extends well beyond the capital deployed to date. Across his multiple placements in Capital B since August 2025, Back has accumulated warrants attached to tens of millions of shares. The September 2 placement alone issued 13,181,030 ABSA units, each carrying four warrants — 52.7 million warrants in total. If Back exercises all warrants from that placement at their respective strike prices (€0.75 / $0.87, €0.98 / $1.13, and €1.27 / $1.47), Capital B would receive approximately €49.4 million (approximately $57 million) in additional capital — without another public fundraising announcement.

That latent capital is significant context for any investor evaluating Capital B’s future accumulation trajectory. Back’s warrants are functionally a committed pipeline of future funding if the stock performs. The company can also trigger an accelerated exercise window if the 20-day volume-weighted average price exceeds 130% of any applicable warrant strike price for 20 consecutive trading days. In effect, Back has structured his participation not as a one-time bet but as a series of forward commitments that scale with the company’s share price.

His public comment after the September 2 placement — noting he had bought more than 25 million ALCPB shares between that week’s raise and the preceding week’s €21 million placement — was characteristically brief: “Let’s go.”

Why Back’s Involvement Is Different

Most corporate Bitcoin treasury companies are backed by institutional investors seeking Bitcoin-correlated equity exposure. Capital B’s major backer is the cryptographer whose 1997 paper on computational proof-of-work is the direct technical ancestor of Bitcoin’s mining algorithm. Satoshi Nakamoto cited Back in Bitcoin’s whitepaper and emailed Back before publishing the paper — making him one of a small number of individuals who can plausibly claim a peer relationship with Bitcoin’s pseudonymous creator.

Back’s current institutional roles span multiple fronts simultaneously. As co-founder and CEO of Blockstream, the Bitcoin infrastructure firm, he oversees development of the Liquid Network sidechain, enterprise Bitcoin infrastructure, and the Jade hardware wallet. Separately, his Bitcoin Standard Treasury Company (BSTR) had been preparing to go public on Nasdaq through a merger with Cantor Equity Partners, a deal structured around 30,021 BTC and up to $1.5 billion in PIPE financing; the merger was terminated in August 2026 citing challenging market conditions for Bitcoin treasury vehicles. His Capital B stake is, against that backdrop, a relatively modest personal conviction bet in European public markets — but its symbolic and financial weight for a Euronext-listed company of Capital B’s scale is considerable.

Treasury Metrics and the Unrealized-Loss Dimension

With 3,521 BTC acquired at cumulative €309.4 million (approximately $357 million), Capital B’s average per-coin cost basis works out to €87,878 (approximately $101,400) per BTC. Current bitcoin prices near €67,000 to €68,000 ($77,000 to $78,500) imply the treasury is carried at a market value of approximately €240.8 million (approximately $277.9 million) — a gap of roughly €68.6 million (approximately $79 million) between what the company paid and what the coins are worth today.

Capital B reports this number honestly; the company’s annual results for 2025, published in April 2026, attributed a €53.9 million net loss primarily to a BTC impairment charge following Bitcoin’s price at year-end 2025. Under FASB-equivalent accounting rules that require marking Bitcoin to market each quarter, the company’s financial statements reflect full asset-price exposure.

This matters for investors in two ways. First, any further decline in Bitcoin’s price widens the gap and increases reported losses — losses that are real in the sense that they represent capital committed at higher prices. Second, the warrant structure works in reverse at lower stock prices: if Capital B’s share price does not reach the warrant strike prices, the warrants expire worthless and the potential €49.4 million ($57 million) in future capital from Back’s September 2 warrants never materializes.

The company also holds 61 BTC segregated for operational needs, excluded from its treasury performance calculations, and tracks a “BTC € Gain” figure — the euro-denominated value appreciation of the bitcoin per share since the start of the year — which stood at €4.2 million (approximately $4.85 million) as of Monday’s filing.

Broader Context: Europe Catches Up

Capital B currently ranks among the top 30 publicly listed companies globally by Bitcoin holdings. At 3,521 BTC, it sits 84 coins behind Germany’s Bitcoin Group SE — which holds 3,605 BTC and leads Europe’s public-company Bitcoin rankings — and holds a fraction of Strategy’s 800,000-plus coins. Within Europe, Capital B is one of the continent’s most active listed Bitcoin accumulators, and its structure is meaningfully different from the US model.

European listed companies face different capital market mechanics. The Euronext Growth Paris market, where Capital B trades, is a lighter-regulatory venue designed for growth companies — requiring disclosure but not the full prospectus burden of the main Euronext market. The ABSA structure Capital B uses is native to French market practice, making it more accessible to European institutional investors than US-style convertible note or STRK-equivalent instruments would be.

Capital B has also announced a subsidiary in Abu Dhabi, indicating it intends to build institutional relationships beyond Euronext Growth Paris. The company’s operating subsidiaries — in data intelligence (IORGA), artificial intelligence, and decentralized technology consulting (Trimane) — generate modest operational cash flows that contribute to the treasury strategy, though the core driver is capital markets activity.

Worth noting: on September 8, the day after this announcement, Capital B is scheduled to execute a 10-for-1 reverse stock split — a standard administrative adjustment for a company whose shares have declined significantly from their 2025 highs above €5.96. Post-split, the warrant strike prices will be restated accordingly (for example, the €0.75 warrant becomes €7.50). The reverse split does not affect the underlying economics of the treasury.

What Can a Shareholder Do With This Information?

Capital B’s total holdings of 3,521 BTC represent concentrated Bitcoin exposure through a leveraged equity structure that trades at the intersection of several risks: Bitcoin price risk, dilution risk from warrant exercises, the performance of the operating subsidiaries, and the reliability of the BTC Yield metric as a proxy for value creation. Investors considering ALCPB or its US OTC equivalent (CPTLF) are not buying Bitcoin — they are buying a claim on a company that holds Bitcoin, with all the capital structure complexity that implies.

The case for the Back-style conviction: if Bitcoin appreciates meaningfully from its current range, the ABSA structure’s warrant pipeline transforms into a powerful accumulation engine — and the current below-average acquisition cost of Monday’s purchase begins to look prescient. The case against: the company’s cost basis is substantially underwater at current prices, dilution from warrant exercises widens the fully diluted share count, and the NAV premium dynamic that made Strategy’s early accumulation accretive has not reliably materialized for Capital B’s stock.

Monday’s announcement did not resolve that tension. It deepened it — with an additional 376 BTC, a new pipeline of potential capital, and the ongoing bet of one of Bitcoin’s original architects that the European listed-equity market is the right venue for the network’s next phase of institutional adoption.

Currency conversions use August–September 2026 ECB reference rate data; all figures are approximate.

Frequently Asked Questions

What is Capital B’s BTC Yield metric, and why does it matter?

BTC Yield measures how much the amount of Bitcoin per fully diluted share has grown over a given period — in Capital B’s case, since January 1, 2026. At 2.17% year-to-date, the company’s Bitcoin-per-share figure has grown by that amount even as new shares are issued to raise capital. A positive BTC Yield means the company is growing its per-share Bitcoin exposure faster than it is diluting shareholders through new issuances. It is a more informative metric than total BTC holdings alone because it accounts for the dilution cost of each capital raise — but it does not account for whether the stock trades at a premium or discount to the value of the underlying Bitcoin.

Who is Adam Back, and what is his connection to Bitcoin’s origins?

Adam Back is a British cryptographer who invented Hashcash in 1997 — a proof-of-work system originally designed to reduce email spam by requiring senders to perform a small computation per message. When Satoshi Nakamoto published the Bitcoin whitepaper in 2008, Back’s Hashcash was the only academic work cited by author name, and Bitcoin’s mining mechanism is a direct adaptation of the Hashcash concept. Back co-founded Blockstream in 2014, one of the primary Bitcoin infrastructure companies, and he remains its CEO. His personal investments in Capital B since August 2025 represent a sustained conviction bet on the European Bitcoin treasury model — backed by someone who helped engineer the system the whole movement depends on.

What risks should investors understand before buying Capital B shares?

Capital B’s aggregate cost basis for its 3,521 BTC is approximately €87,878 (approximately $101,400) per coin, well above the current market price of approximately €67,000 ($77,500) — meaning the treasury carries substantial unrealized losses at current prices. The warrant structure creates future dilution: if all warrants from Back’s September 2 placement are exercised, the diluted share count grows and additional shares are issued. The BTC Yield metric measures per-share growth but does not directly measure whether the market price of ALCPB reflects that growth. The company trades on Euronext Growth Paris, a lighter-regulatory venue than the main Euronext market, which limits some investor protections available on larger exchanges. US investors can access shares via the OTC market as CPTLF, but liquidity and regulatory disclosures differ from Euronext trading.

Can US investors access Capital B shares, and what should they know?

Yes — Capital B trades on the US OTC market as CPTLF. OTC trading involves lower liquidity, wider bid-ask spreads, and less regulatory oversight than a listed US exchange. The shares are denominated in euros and subject to currency exchange risk for US-dollar investors; at current rates of approximately 1 EUR = $1.15 USD, exchange movements add another variable to returns. The 10-for-1 reverse stock split scheduled for September 8 will not change the economic value of existing holdings, but it will restate the share price and warrant terms proportionally. Before investing in any foreign-listed company whose primary business is holding a volatile asset, consulting a financial advisor is appropriate.