Why Bitcoin Treasury Companies Exist
For years, UK investors who wanted Bitcoin exposure inside a tax-advantaged wrapper had no clean option. The FCA banned retail access to crypto ETPs in January 2021, citing volatility and consumer harm. That meant no Bitcoin in your ISA, no Bitcoin in your SIPP, and no regulated exchange-traded product to bridge the gap. If you wanted Bitcoin exposure inside a pension, you had two imperfect choices: buy shares in crypto-adjacent companies (miners, exchanges, blockchain funds) that correlated loosely with Bitcoin, or hold spot crypto outside the tax wrapper entirely and accept the capital gains liability.
Bitcoin treasury companies emerged to fill this structural gap. The model, pioneered by Strategy (formerly MicroStrategy) in the US, is straightforward: a publicly listed company acquires Bitcoin on its balance sheet, and the equity becomes a Bitcoin proxy. Buy the shares in a SIPP, and you have tax-advantaged Bitcoin exposure through a regulated instrument on a recognised exchange.
The UK landscape has since evolved. In October 2025, the FCA lifted its ban and allowed retail access to regulated crypto ETPs, provided they are physically backed and listed on an FCA-approved exchange like the London Stock Exchange. Bitcoin ETPs are now eligible for both ISAs and SIPPs — though from April 2026, new purchases in ISAs will be restricted to Innovative Finance ISAs rather than standard Stocks and Shares ISAs. Major providers including WisdomTree, 21Shares, Bitwise, and BlackRock (via iShares) now offer regulated Bitcoin ETPs accessible to UK retail investors.
This matters because it partially resolves the access problem that justified treasury companies in the first place. UK investors can now hold regulated, physically backed Bitcoin exposure inside a pension without going through a corporate equity proxy. The question becomes: if you can hold Bitcoin directly through an ETP in a SIPP, why would you ever buy a treasury company instead?
The answer lies in what treasury companies can do that ETPs cannot: use corporate finance to create BTC yield per share.
How Treasury Companies Create Value
A Bitcoin ETP gives you linear exposure. You own one unit of the ETP, it tracks the Bitcoin price. If Bitcoin goes up 50%, your ETP goes up roughly 50% (minus fees). There is no leverage, no capital structure to exploit, and no mechanism to grow your Bitcoin exposure per unit over time.
A treasury company can do something structurally different. It can raise capital — through equity issuances, convertible bonds, or other instruments — and use that capital to acquire more Bitcoin. If the capital is raised at a premium to the company's net asset value (i.e., the market values the company higher than the Bitcoin on its balance sheet), then each raise is accretive to existing shareholders in Bitcoin-per-share terms.
This is the core value proposition. A well-run treasury company doesn't just hold Bitcoin — it accumulates Bitcoin per share over time, using the premium the market assigns to the wrapper as a financing tool. Strategy has demonstrated this model at scale. SWC, the UK's largest public Bitcoin holder, is attempting to replicate it on the London Stock Exchange.
The mechanism also works in reverse. If the company trades at a discount to its net asset value — meaning the market values the equity at less than the Bitcoin on the balance sheet — then any capital raise is dilutive. Shareholders would be better off buying spot Bitcoin directly. This is why the mNAV metric matters so much.
The mNAV Framework
mNAV — market cap to net asset value — is the single most important metric for evaluating a Bitcoin treasury company. It measures whether the market is paying a premium or a discount for the corporate Bitcoin wrapper.
mNAV > 1.0x means the market values the company above its Bitcoin holdings. The premium reflects the market's willingness to pay for the wrapper's perceived advantages: management quality, capital markets access, accumulation track record, tax wrapper eligibility, or narrative momentum. At premium mNAVs, equity raises are accretive — the company can issue shares above NAV and buy more Bitcoin per existing share.
mNAV < 1.0x means the market is discounting the company below its Bitcoin. This can happen when Bitcoin price declines sharply (eroding confidence), when dilution has been excessive, when management credibility is questioned, or when the narrative around treasury companies cools. At discount mNAVs, equity raises are destructive — issuing shares below NAV dilutes existing holders' Bitcoin-per-share exposure.
mNAV = 1.0x is the pivot. At exactly 1.0x, you are paying face value for the Bitcoin with no premium and no discount. The company is worth exactly what its Bitcoin is worth.
The practical question for an investor is: at what mNAV does it make sense to buy the treasury company equity versus buying spot Bitcoin or a low-fee ETP?
The Arxonic buy rule is simple: acquire SWC via SIPP when mNAV ≤ 1.25x. If mNAV exceeds 1.25x, buy spot BTC directly.
The logic behind 1.25x as the threshold: the tax advantages of SIPP wrapping (income tax relief on contributions, tax-free growth, no capital gains tax) are worth a modest premium above NAV. But the premium must be modest. At 1.5x mNAV, you are paying 50% above the value of the underlying Bitcoin for the privilege of the wrapper — and at that point, the tax benefits are consumed by the premium. The exact threshold depends on individual tax circumstances, contribution size, and time horizon, but 1.25x captures the range where the wrapper benefit justifies the cost for most UK investors.
The UK Landscape
The UK Bitcoin treasury sector is nascent and concentrated. As of early 2026, the major players are:
The Smarter Web Company (SWC) is the dominant name. Founded in 2009 by Andrew Webley as a web design agency, the company pivoted to a Bitcoin treasury strategy in 2025. It IPO'd on the Aquis Exchange in April 2025, becoming the UK's best-performing equity that year, before uplisting to the London Stock Exchange Main Market in February 2026. SWC holds over 2,500 BTC — the largest UK public company by Bitcoin holdings and the 29th largest globally. With Bitcoin trading in the $66,000–70,000 range as of late March 2026 — down roughly 48% from its October 2025 all-time high of approximately $126,000 — the position is materially underwater, representing an unrealised loss of approximately 40%.
SWC has been the most aggressive UK player in replicating Strategy's capital markets playbook, including the issuance of a $21 million Bitcoin-denominated convertible bond ("Smarter Convert") in August 2025, structured in partnership with Paris-based asset manager TOBAM. The 12-month bond, convertible at a 5% premium to the share price, was the first of its kind in UK capital markets.
Beyond SWC, the UK landscape includes Satsuma (approximately 1,149 BTC), Phoenix Digital Assets (~247 BTC), B HODL (~100 BTC, listed on Aquis under "HODL"), Connecting Excellence Group (~52 BTC), and Vaultz Capital among others. These are overwhelmingly small-cap or micro-cap companies. None approaches SWC's scale.
The sector faces a credibility challenge. K33 Research has found that one in four public Bitcoin treasury companies globally now trade below the value of their Bitcoin reserves.
The Smarter Convert and Capital Structure Innovation
SWC's convertible bond with TOBAM is worth examining because it represents the first attempt to bring Strategy-style capital structure innovation to the UK market.
The structure works as follows: TOBAM invested $21 million through three managed funds. The bond is denominated in Bitcoin, interest-free, and convertible into SWC shares at a 5% premium to the August 2025 share price. After a six-month lock-up, TOBAM can convert at any time. If the share price rises 50% above the conversion price for 10 consecutive trading days, SWC can force conversion. If no conversion occurs after 12 months, SWC repays 98% of the bond principal, adjusted to the prevailing Bitcoin price.
This structure allows SWC to raise capital above market without immediate dilution, while giving TOBAM both equity upside and Bitcoin-denominated downside protection. If all bonds convert, approximately 7.7 million new shares would be issued.
The broader question is whether UK capital markets have the depth and appetite for these instruments at scale. Strategy operates in the US, where capital markets are deeper, institutional familiarity with convertible structures is greater, and the investor base for Bitcoin-adjacent products is larger. SWC is attempting the same playbook on the LSE with significantly lower liquidity.
The Decision Framework
For UK investors considering Bitcoin exposure within a tax-advantaged account, the decision tree is now more nuanced than it was twelve months ago:
Step 1: Do you want tax-advantaged Bitcoin exposure? If not, buy spot BTC directly (self-custody or regulated exchange). No premium, no counterparty risk, no management overhead. This is the simplest and cheapest option.
Step 2: Is a regulated ETP available in your SIPP or ISA? Since October 2025, yes. Physically backed Bitcoin ETPs from WisdomTree, 21Shares, Bitwise, and BlackRock are available on the LSE. Fees are typically 0.15–0.35% per year. This gives you near-linear Bitcoin exposure inside the tax wrapper with minimal tracking error. For most investors, this is now the default answer.
Step 3: When would a treasury company be preferable? Only when the mNAV creates an opportunity that the ETP cannot replicate. If a treasury company trades at or below NAV, you are effectively buying Bitcoin at a discount to market price through the equity. If the company has a credible accumulation strategy and accretive capital markets programme, your Bitcoin-per-share exposure may grow over time — something no ETP can offer. The trade-off is management risk, dilution risk, liquidity risk, and concentration in a single company rather than pure Bitcoin exposure.
Step 4: The Arxonic buy rule. mNAV ≤ 1.0x → Strong buy via SIPP. mNAV 1.0x–1.25x → Buy via SIPP. mNAV > 1.25x → Buy spot BTC or a low-fee ETP instead.
Step 5: Is the company accretively accumulating? Check whether Bitcoin per share is growing over time. If the company is diluting shareholders without proportionally increasing BTC holdings, the model is broken regardless of mNAV. Accumulation track record is the second most important metric after mNAV.
When the Model Breaks
The Bitcoin treasury model has failure modes that investors should understand before allocating:
Bitcoin price declines erode the thesis from multiple directions. When Bitcoin falls, NAV falls, market capitalisation often falls faster (widening the mNAV discount), the company's ability to raise accretive capital evaporates, and existing debt obligations become more burdensome. SWC's experience is instructive: having accumulated at high average costs, the roughly 48% decline in Bitcoin from its all-time high has turned the position deeply underwater and contributed to a significant decline in market capitalisation from highs.
Dilution without accretive deployment. If a company raises capital at premium mNAVs but fails to deploy it efficiently into Bitcoin, or raises at discount mNAVs because it has no choice, existing shareholders are worse off than if they had simply held spot BTC.
Management and governance risk. These are small, founder-led companies making concentrated, leveraged bets on a single volatile asset. Governance structures, compensation alignment, and decision-making processes matter enormously.
The ETP competitor. Now that regulated Bitcoin ETPs are available in UK SIPPs and ISAs, treasury companies must justify their existence as a superior wrapper. If ETPs offer pure Bitcoin exposure at 0.25% annual fees with no dilution risk, treasury companies need to demonstrably create value above and beyond simple Bitcoin price tracking. Accretive accumulation is the only way to do this.
The Arxonic Position
SWC is held within a SIPP as a Bitcoin proxy, representing approximately 16% of the Arxonic portfolio. The position was established under the mNAV ≤ 1.25x buy rule.
The thesis is straightforward: SWC provides tax-advantaged Bitcoin exposure inside a pension wrapper, with the optionality that accretive capital markets activity could create Bitcoin yield per share over time. The buy rule enforces discipline — when the premium to NAV is too high, capital goes to spot BTC instead.
The position would be reconsidered if: SWC consistently fails to accumulate Bitcoin per share; management pursues dilutive raises at discount mNAVs; governance issues emerge; or if Bitcoin ETP products in SIPPs prove to offer strictly superior risk-adjusted exposure that eliminates the case for the corporate wrapper entirely.
The broader observation is that the UK Bitcoin treasury sector is very early, very concentrated, and very high-risk. SWC is the only player at meaningful scale. This is not a low-conviction allocation — it is a deliberate bet that the SIPP wrapper plus the optionality of accretive accumulation justifies the additional risk over a simple ETP.