The hidden banks behind crypto cards

A look at the BIN-sponsor concentration inside 141 active crypto-linked cards.

On 21 January 2026, Poland's Financial Supervision Authority pulled the payment-institution license of a small Polish company called Quicko sp. z o.o. Thirteen days later, three crypto cards in different parts of the world stopped working at the same time.

CEX.IO Card. Trustee Plus. IN1. None of the parent brands had failed. None had been sanctioned. None had been hacked. The single thing they shared was the bank-equivalent that printed their plastic, and that bank-equivalent had just lost its license.

If you owned one of these cards, your only warning was a support article. Piece the timeline together from the public record and you get the problem in miniature. On 21 January the KNF notice goes up, in Polish, on a supervisory site a Trustee Plus user in Kyiv or Lisbon has no reason to read. On 29 January a support post lands (CEX.IO's is at support.cex.io/en/articles/13460417) saying the card will stop. Five days later, on 3 February, it stops mid-month, with whatever float had been topped up for everyday spending frozen until the 30 April wind-down. The balance is not necessarily lost. But the person holding it did nothing wrong, picked a reputable brand, and never signed anything with a Polish company called Quicko. The gap between who you think you contracted with and who actually holds your license is what this piece is about.

This is the structure of a sponsor failure cascade. It is not new. Wirecard collapsed in June 2020 and took Crypto.com's original Visa card, Binance's original Visa card, TenX, Monolith, and Wirex's old Visa product with it. Metropolitan Commercial Bank exited crypto in January 2023 and BitPay's prepaid Mastercard is still down. Moorwand exited crypto sponsorship in 2023 and Bybit had to migrate its EEA card to a French issuer.

The Quicko cascade is small. The Wirecard cascade was huge. They share one structural property. A bank or licensed payment institution that never appears on the front of your card, that you've never heard of, that you never signed up with, is the thing that makes the card work. When the regulator pulls that license, the card stops working.

This is concentration risk. In crypto, it has been quietly getting worse.

What a BIN sponsor actually is

Visa and Mastercard run two-sided card networks. To put your logo on a card and have that card work at any merchant on the network, you have to be a Principal Member. Principal membership requires a banking or e-money license, capital, dedicated compliance staff, and several million dollars a year in network fees. There are a few hundred principal members of each network globally.

Most crypto companies are not principal members. They rent the membership.

The rental contract is called BIN sponsorship. The "BIN" is the Bank Identification Number, the six-digit prefix that starts every card number and tells the network which member is liable for what comes next. The sponsor is the principal member whose BIN is being rented. The crypto company is the program manager: it sets the brand, the loyalty mechanics, the integration with the user's wallet, the customer support. The sponsor handles compliance, settlement, and the network relationship.

This split is hidden in cardholder agreements that almost nobody reads. The Phantom Cash agreement, on bridge.xyz, opens with the words "This Cardholder Agreement is between Bridge Ventures LLC and you for the Lead Bank Prepaid Visa Card... issued to you by Lead Bank, a Missouri state-chartered bank." Lead Bank is the sponsor. Bridge is the program manager. Phantom is the brand. Three layers, and only one of them appears on the card itself.

A few side roles confuse things further. Marqeta, often described in trade press as Coinbase Card's "issuer," is in fact the processor that operates the issuing rails. The actual BIN sponsor for Coinbase Card is Pathward, NA, a US bank formerly named MetaBank. Processor and sponsor are different roles. Confusing them is the most common error in casual crypto media coverage.

The other recurring confusion is brand versus entity. There are two unrelated companies called Rain in crypto-card infrastructure: Rain Liquidity Inc., a US Visa principal member and program manager that became Mastercard principal on 4 May 2026, and Rain Management WLL, a Bahrain-licensed crypto exchange that touches some Middle East product launches. These are different companies. The dataset accompanying this article treats them as separate entities.

How this dataset was built

The dataset behind this article tracks 141 crypto-linked cards available somewhere in the world as of May 2026. For each card, the goal was to identify the BIN sponsor named in the cardholder agreement or terms-and-conditions document on the card's own website.

This sounds simple, but agreements bury the sponsor's name wherever is least convenient — the first sentence on a good card, an apply-only PDF or a chargebacks clause three documents deep on a bad one, and on a handful, nowhere reachable from outside the application flow at all.

The 141 cards fall into three rough tiers by how reachable the sponsor name is. Around 79 have a public T&C naming the sponsor verbatim — though on a 16 May 2026 spot-audit of 32 of them, only 14 were re-verifiable that day, so treat these as "documented at least once at primary source," to be re-checked on publication. Around 34 rest only on an older T&C, a press release, or a regulator filing, and are flagged MEDIUM confidence. The remaining ~25 name no sponsor publicly: some never have, some removed the disclosure when their sponsor changed, and some (post-Union54) now treat naming it as a risk in itself.

Cutting across all three tiers is a "circumstantial" label for sponsors inferred from the program manager rather than stated outright. This article quotes circumstantial figures only as upper-bound estimates, never as facts, and the upper-bound counts later draw on those cards too. The full 141-card comparison dataset is at sweepbase.net/dataset; the BIN-sponsor attribution specific to this piece lives in the tables here, the appendix, and the Sources section, not in that file.

The numbers

The first instinct when measuring market concentration is to compute a Herfindahl-Hirschman Index across the whole market. For 141 crypto cards, that calculation gives an HHI of roughly 400 to 500. The US Department of Justice treats anything below 1,500 as unconcentrated, anything between 1,500 and 2,500 as moderately concentrated, anything above 2,500 as highly concentrated.

By this measure, the global crypto-card market is fine.

Two things before the numbers. First, I have card counts, not transaction volumes or cardholder numbers, so the honest primary measure here is a concentration ratio — what share of a segment's cards run through its single largest issuer — not a true HHI. Second, where a familiar HHI-style index appears below, it is just those same counts squared into the index antitrust uses; the DOJ's 1,500 / 2,500 bands are a yardstick for intuition, not a finding about market power, which would need data no one here has.

The global measure is misleading. Crypto cards do not compete in a single market. A US dollar self-custody card issued out of Puerto Rico is not competing with a Brazilian real card issued out of Buenos Aires for the same customer. Once you split the dataset into regions and product types, which is the choice a user actually faces when picking a card, the concentration picture changes sharply.

US self-custody and stablecoin cards

This is the segment where most of the recent product launches have happened: Ether.fi Cash, Cypher, Solayer, Tangem Pay, Phantom Cash, KAST, Tuyo, Avalanche Card, Moonwell, Spritz, and others. Roughly 22 cards in active distribution.

Within this segment, two issuing entities anchor most cards. The first is Third National, the issuer Rain names on its Visa cards — identified in the cardholder agreements of Cypher, Solayer, and Tangem Pay. (Rain's own disclosures describe cards "issued by Third National," with fiat settlement handled behind the scenes by SSB, an FDIC member. Third National is the trading name of Nimbus LLC, a Puerto Rico money transmitter (NMLS #2612780) — not a bank, and not FDIC-insured. An earlier description of it as a Tennessee state-chartered bank was wrong.) Spritz names only "Rain", leaving the issuer inferred. On roughly thirteen further cards built on top of Rain — the Visa Principal program manager that contracts directly with Third National — it is the implied but not publicly named issuer, bringing its footprint here to around seventeen of the twenty-two (both numbers approximate). Ether.fi Cash is in that circumstantial group. The second is Lead Bank, a Missouri state-chartered bank, named verbatim in the cardholder agreements of Phantom Cash, Wayex, Airtm, and Fuse — all four on Bridge, the program manager Stripe acquired and closed on 4 February 2025.

The shape of that is easier to see than to read. Roughly twenty-two distinct brands, almost all of them launched in the last two years, funnel down to two issuers.

Counting only the seven cards with a sponsor named verbatim — four on Lead Bank, three on Third National — the concentration among just those already gives an index above 5,000. Folding in the roughly thirteen further cards that run on Rain, which lifts Third National to around seventeen of the twenty-two across the full segment, pushes the index above 6,000. Both passes clear the DOJ "highly concentrated" band by a wide margin on a count basis, so the conclusion does not rest on the softer attribution. If Third National's issuing arrangement were suspended or restricted (there is no public indication that it will be), the practical effect would be the simultaneous wind-down of most US-issued self-custody crypto cards.

One honesty note belongs here, because this is the loudest number in the piece. Third National is named verbatim on only three of these cards — Cypher, Solayer, Tangem Pay. The four Lead Bank cards are separately documented in the appendix, but the jump from three to "~17 of 22" on Third National runs through circumstantial Rain attribution, not seventeen separate cardholder agreements. So the US segment is the largest concentration claim but not the best-documented one. The best-documented concentration in this article is the European side below, where Monavate is named verbatim across five cards and the corporate ownership is a matter of public filing. Read the US figure as the strong-but-inferred case and the EU figure as the strong-and-sourced one.

EU and UK self-custody cards

The European side of the same story is even more concentrated. Around 12 cards, most of them on one sponsor. The cardholder agreements of Gnosis Pay, OKX EEA, Krak (Kraken's spending card, UK and EEA), Ledger's CL Card (EU side), and 1inch all name Monavate as the sponsor. Monavate Limited is a UK FCA-authorised e-money institution; UAB Monavate is the Lithuanian sister entity. Both are owned by Monavate Holdings Ltd., which in turn is part of W3C Corp.

On 24 November 2025, Exodus Movement Inc. announced a definitive agreement to acquire W3C Corp for $175 million. It did not close on those terms. After Exodus sued to force completion and called the loans it had already extended, UK receivers were appointed over W3C's operating subsidiaries, and on 1 May 2026 Exodus completed the takeover through them — credit-bidding its debt for $76.27 million, the exact balance owed, with a separate Baanx US purchase taking the restructured total to roughly $106 million with the earn-out. (The full mechanics are in the Sources note; a receivership credit-bid and the original negotiated stock purchase are not the same kind of transaction.)

With closing complete, a single self-custody crypto wallet brand now owns the BIN sponsor for most of its EU self-custody competitors — including the sponsor behind Krak, the spending card of Kraken, Exodus's largest competitor.

As a competition story, it has gone almost entirely unreported. The Exodus / W3C / Monavate / Baanx structure has not been treated by trade press or regulators as a competition concern, in part because the parent-subsidiary structure is opaque from the outside and in part because the final purchase price was small relative to typical antitrust thresholds.

LatAm

LatAm is smaller and a little more diversified, though only on the surface. Six cards. Pomelo, an Argentine BaaS provider, sponsors three (Lemon in Argentina and Peru; Ripio in Argentina). Rain via Third National sponsors approximately two more. Bridge via Lead Bank sponsors Airtm. Bitso's Mexican card was discontinued in May 2025 per Bitso's own support FAQ. The resulting count-based index is roughly 3,900. That is above the DOJ 2,500 line on a count basis, with single-failure exposure to two US issuers and one Argentine BaaS.

Canada

Two cards tracked. Both sponsored by Peoples Trust Company. A de facto monopoly, though the Canadian crypto-card market is small enough that this is not surprising. The practical effect is that any Canadian crypto card uses Peoples Trust whether the consumer knows or not.

Asia (APAC)

APAC is the segment where no honest single number is reachable. About ten cards, most of which do not name their sponsor on any public page. What concentration is visible sits with three principal members in Singapore and Hong Kong: StraitsX, DCS Card Centre (the former Diners Club Singapore, now sponsor for Morph, Decard, and the APAC side of Jupiter), and Reap. The transparency deficit is itself a structural feature of the APAC crypto-card market, not an oversight in the dataset.

The top sponsors

The top sponsors by attributed card count (upper-bound, circumstantial included) are in Table 2 below. One detail the table understates: Foris Group, which holds five regional licenses for Crypto.com's own cards across the UK, EU, Australia, Singapore, and Brazil, is the rare crypto company that sponsors itself.

The pattern is consistent across regions: a small number of mid-size banks doing most of the issuing, no megabank involvement at all, and most of the public discussion of "crypto card competition" treating the front-of-card brands as substitutable when in fact two different brands are often two skins on the same regulated entity.

Why concentration matters: the cascade pattern

The argument against caring about BIN sponsor concentration is that this is just back-office infrastructure. Banks fail, other banks pick up the cards, the brand on the front of the plastic absorbs the friction, and the user is mostly insulated.

History does not support this picture.

Wirecard filed for insolvency in Munich on 25 June 2020. The date is verbatim from Wirecard's own MAR Article 17 disclosure. Wirecard had been the BIN sponsor for a long list of European fintech card programs. Within weeks, the Crypto.com Visa card was no longer working in the EEA. Binance's original European Visa was no longer working. TenX was effectively done. Monolith had to wind down. Wirex's old Visa product went away, and Wirex eventually became a Mastercard Principal Member directly in July 2020, one of the few crypto companies to do so. Curve, ANNA, Pockit, Soldo, and Cryptopay all had to either migrate or pause. The exact number of disrupted fintech-card programs is reported in secondary press as somewhere between thirty and seventy. There is no primary source for an exact number, in part because the FCA-led "Special Administration" of Wirecard's UK subsidiary classified affected firms differently depending on whether they had safeguarded funds correctly.

The other four cases in the table vary in speed and blast radius. Metropolitan Commercial Bank's January 2023 exit from crypto left BitPay's prepaid Mastercard down to this day and pushed Uphold's US card onto Cross River. Moorwand's 2023 exit forced Bybit's EEA card onto Harmoniie SAS, a French ACPR-authorised EMI. Union54's Mastercard suspension in July 2022 did something more lasting than any single migration: after it, African and LatAm operators became reluctant to name their sponsor on public pages at all, which is why the transparency deficit in those regions reads as structural rather than coincidental. And Modulr's September 2025 step-back from crypto marketing is the slow kind — a steady migration of programs onto a smaller set of remaining sponsors (Striga, Wallester, Pervesk, DiPocket), concentrating those names rather than shocking the market in a week.

And then Quicko, in January and February 2026. KNF revoked the license on 21 January. CEX.IO, Trustee Plus, and IN1 stopped processing on 3 February. The wind-down deadline was 30 April 2026, now passed. Quicko itself is smaller than any of the earlier examples, but it is the most recent and most documented case. The KNF revocation notice is in Polish, the CEX.IO and Trustee Plus support announcements are in English and unambiguous, the dates line up.

The pattern is the same in every case. The card brand does not fail. The sponsor fails. The card stops working anyway.

The customer-facing brand absorbs the support load and, if it survives, migrates to a new sponsor at significant operational cost. If it does not survive, the product disappears and the customer balance can end up as a creditor claim in whichever jurisdiction the sponsor was wound up — though, as the next section explains, that is the worst case rather than the usual one.

What actually happens to your money

The phrase "creditor claim" needs a caveat, because it is the part most likely to push a reader to the wrong conclusion. In most of these cascades the customer did not lose the money. They lost access to it for a while.

In the EU and UK, the e-money institutions and program managers discussed here operate under safeguarding rules. Customer funds are held in segregated safeguarding accounts at a separate bank, not on the failed firm's own balance sheet, so they are not supposed to be reachable by its general creditors. Safeguarding is not deposit insurance, and access can still be frozen for weeks or months during an administration while a trustee reconciles balances, but the starting legal position is that the money is the customer's, not the estate's. In the United States, prepaid programs structured for it can carry FDIC pass-through insurance, but only against failure of the sponsor bank itself, only when the account is titled to pass through, and not against insolvency of the program manager or fintech sitting in the middle. That middle-layer gap is what stranded customer balances in the 2024 Synapse collapse.

So the honest version of the risk reads like this. The likely harm from a sponsor failure is loss of access, a forced migration to a new card, and a balance frozen during wind-down. The unlikely-but-not-impossible harm is a genuine shortfall, which is what happens when safeguarding was done badly. The FCA's special administration of Wirecard's UK arm sorted firms on exactly that line: who had safeguarded correctly, and who had not.

Why your bank card doesn't do this to you

A fair objection at this point: ordinary bank cards rest on sponsors and processors too. Your debit card runs through a card network, a processor, and an issuing bank, and most people could not name two of the three. So why does a Chase or a Barclays customer never live through the Quicko experience?

Part of the answer is what sits at the bottom of the stack. A high-street debit card is usually issued by an insured deposit-taking bank, wrapped in a resolution regime built for continuity. When a US bank fails, the FDIC resolves it, and the standard route is a purchase-and-assumption: a healthy bank takes on the failed bank's deposits and accounts, and the regulator's stated aim is continuity for the failed bank's customers — which in the cleanest cases means access is preserved over a single weekend. (The FDIC's own materials describe customer continuity as the goal of a P&A; they do not separately promise that every card program keeps running, so read this as the resolution regime's intent, not a guarantee for any one card.) Card portfolios also change hands in an orderly way outside of failure — issuers buy and sell card books as routine transactions, with cardholders carried across rather than cut off. (Congressional Research Service overview.)

The crypto cards in this article mostly do not sit on insured deposit banks. They sit on e-money institutions and payment institutions, which hold customer money under safeguarding rules rather than deposit insurance, and — this is the key asymmetry — there is no resolution regime that lines up a successor when one of them loses its license. When the KNF withdrew Quicko's authorisation, no regulator arranged a new sponsor, ported the balances, or guaranteed continuity; a licence revocation for cause is a different, messier event than an insured-bank failure even in traditional finance. The licence is pulled, and the cards built on it simply stop. Same plumbing, but no equivalent of the FDIC standing behind it: the orderly-transfer machinery that can make a bank failure nearly invisible to cardholders does not exist for a payment institution's BIN-sponsorship book.

The honest counter-arguments

A few things should be said in fairness.

Most of the concentration identified here is at small or mid-sized institutions. Third National, Lead Bank, Monavate, Wallester, Fiat24, Cross River, Pomelo, and the rest are not systemic; none is too-big-to-fail in any country. None has been recently sanctioned. The risk of any single one of them failing in a given year is not zero, but it is not catastrophic either. Wirecard and Quicko are at the tails of the distribution, not the median.

The most alarming readings also rest on the smallest samples — Canada is two cards, LatAm six — so the weight belongs on the US and EU/UK figures, drawn from twenty-two and twelve cards.

Concentration also enables things. A specialised crypto-friendly sponsor bank can build internal compliance tooling that a generalist bank cannot. The fact that Lead Bank, Third National, and Cross River have repeatedly approved stablecoin-funded card programs is part of why stablecoin spending has scaled at all. If the market were perfectly distributed across two hundred sponsors that each understood crypto poorly, the cost of program approval would rise and the time-to-market would lengthen.

The transparency deficit cuts both ways. From a consumer standpoint, knowing your sponsor matters because it tells you which regulator has jurisdiction if something goes wrong. From an operator standpoint, hiding the sponsor reduces the risk of a Union54-style policy contagion where one fintech's fraud problem closes the sponsor for all other fintechs.

The Exodus / Monavate deal increases concentration, but it may also improve the product: vertically integrated wallet-and-issuer stacks can ship faster than two-party joint ventures, though that is an expectation this dataset does not measure. Whether the trade is good depends on whether you weight market structure or user experience.

None of this changes the underlying observation. The crypto-card market looks competitive at the front-end. The back-end is much more concentrated than the front-end suggests, and on the evidence here the gap has been widening.

One last piece of perspective for anyone actually shopping for a card. Sponsor concentration is a tail risk: it bites on the rare day a regulator acts, not on an average Tuesday. The cost you pay every time you tap is the crypto-to-fiat conversion spread and the FX markup, which we break down in our guide to hidden FX fees. A sensible reader weighs both, and usually weighs the everyday cost first.

If you want to act on this rather than just worry about it, the exposure is easier to manage than to measure. Find out who holds your balance and which regulator would step in if the issuer failed; the better cardholder agreements say so plainly, and the ones that bury it are telling you something too. Treat the card as a way to spend, not a place to store value, so a wind-down freezes a small float instead of your savings. And if real money runs through your cards each month, avoid routing all of it through one sponsor — Quicko took down three unrelated cards in a fortnight, and the people who barely noticed were the ones already carrying a second card on a different rail.

There is also a modest fix available to regulators and networks. Much of the disclosure problem in this article is self-inflicted: the sponsor and its regulator already exist in a contract somewhere, just buried in an appendix or a PDF generated at the end of the application flow. A rule requiring program managers to name the BIN sponsor and its home regulator on the first screen of the cardholder agreement — the way a fund must name its custodian — would let a buyer see the concentration this piece had to reverse-engineer, and let a user who already holds the card know which regulator to watch before anything goes wrong. Disclosure is not a cure: mandated terms still get buried, and a "first screen" rule would face the usual UX and legal pushback. But it is a transparency change, not a structural one — it forces no one to diversify, only to disclose — and it would at least have given a Trustee Plus user more than a Polish-language notice they were never going to read.

Appendix: per-card sponsor attribution (verbatim tier)

The whole thesis rests on per-card sponsor attribution, so the cards named verbatim in the text are listed here with the disclosure each one comes from. This documents the verbatim tier only — the cards whose issuer is stated in their own cardholder agreement or terms. Circumstantial and upper-bound figures elsewhere in this piece are estimates and are not in this table. "Re-fetched 2026-06-23" means the disclosure was confirmed at primary source on that date; "named, not re-fetched" means the attribution is from the card's agreement but was not independently re-pulled in this pass.

Sources & notes

1. Wirecard insolvency: the company's own MAR Article 17 disclosure via BaFin (25 June 2020).
2. Quicko licence revocation: Poland's KNF (21 January 2026). CEX.IO customer notice at support.cex.io/en/articles/13460417; Trustee Plus shutdown announcement, 29 January 2026.
3. Monavate authorisation: UK FCA register, with UAB Monavate as the Lithuanian sister entity.
4. Exodus / W3C: definitive agreement announced 24 November 2025 ($175M); suit against W3C and Garth Howat to compel completion filed in the Delaware Court of Chancery 13 April 2026; closing through UK receivers announced 1 May 2026 ($76.27M for Monavate Holdings + Baanx.com, plus $5M and up to $25M deferred for Baanx US Corp). From the parties' own filings and releases.
5. Moorwand migration: Bybit's EEA card moved to Harmoniie SAS, a French ACPR-authorised EMI. Bitso's Mexican card discontinuation per Bitso's support FAQ, May 2025.
6. Concentration thresholds: the US DOJ Horizontal Merger Guidelines (the 1,500 and 2,500 HHI bands).
7. Union54 BIN suspension: African fintechs halted USD virtual cards after a chargeback-fraud surge on Union54's Mastercard BIN, July 2022, per TechCrunch.
8. Synapse collapse: the 2024 failure of the Synapse banking-as-a-service intermediary froze fintech customer balances and exposed the program-manager gap in FDIC pass-through coverage, per TechCrunch.

Data verified as of June 2026. The Sources section lists the primary records behind the cascade events and the deal timeline; per-card sponsor names come from each card's own cardholder agreement, and the safeguarding and FDIC passages are general regulatory background, not card-specific guarantees. Figures credited to a named outlet or filing are cited inline.

This is independent research, not financial advice. Sweepbase's affiliate relationships are listed on our disclosure page.

Changelog. v3.5 (25 June 2026): confirmed Third National's identity as the trading name of Nimbus LLC, a Puerto Rico money transmitter (NMLS #2612780), not a bank and not FDIC-insured; replaced the "charter unconfirmed" hedge with the confirmed fact and removed a stray "issued out of Tennessee" geographic reference, after a full registry re-audit of every named issuer. v3.4 (23 June 2026): lossless trim + humanizer touch after a full math re-check (all concentration ratios, HHI-style figures, and verbatim counts reconcile). Removed only restated content — the counter-arguments small-sample paragraph (it repeated the Table 1 caption), a rhetorical filler line, and the Exodus deal date/mechanism in the counter-arguments (already stated in the EU section). No fact, source, or argument dropped. v3.3 (23 June 2026): length trim (~6,800 → ~6,100 words) plus a math-correctness pass. Corrected the funnel's Lead Bank count (~6/22 → ~4/22, since 17+6 exceeds the 22-card segment), the EU/UK row (Monavate ~12/~100% → ~10/~83%, matching Monavate's ~10-card total), the US index (single ~6,300 instead of a denominator-mixing range), and the US honesty note (it is Third National's count, not the whole segment, that leans on inference). Trimmed without dropping facts or sources: six cascade paragraphs condensed to two (Table 3 carries the rest), methodology compressed, the top-sponsor prose list removed (Table 2 covers it), the Exodus mechanics shortened (figures remain in the Sources note), the redundant "what the data is" section cut, and the brand-vs-entity figure removed (the funnel makes the point). v3.2 (23 June 2026): metric-honesty + de-hedge pass. Demoted the HHI to a count-native concentration ratio (share of a segment held by its single largest issuer) as the primary measure, with the HHI-style index kept only as a secondary, derived column; shortened the methodology caveat; added an honesty note that the US "~17 of 22" reading rests on circumstantial Rain attribution while the EU/Monavate concentration is the best-documented; fixed a "two banks" phrasing to "two issuers" (Third National's charter is unconfirmed); condensed this changelog. v3.1 (23 June 2026): clean-slate-critique pass — corrected the unverified "Third National = Tennessee state-chartered bank"; re-confirmed the Exodus price and the Lead Bank/Bridge and Monavate attributions at primary source; added the card-count caveat and a per-card verbatim-tier appendix; reframed the bank comparison to insured-bank-vs-EMI; removed false precision; replaced the Figure 2 bar chart with a conclusion-only contrast. v3.0 (23 June 2026): critique-driven additions — reconstructed intro timeline, bottleneck funnel (Fig 1b) and brand-vs-entity view (Fig 1c), the "why your bank card doesn't do this" section, and a disclosure proposal. Earlier history (v1.0, 18 May 2026, through v2.5) is condensed; the full log lives in the project repository.

About the author. Mihail B. runs Sweepbase, an independent crypto-card comparison and research project tracking 141 active cards across regions, networks, and BIN sponsors. New research drops are announced on his personal LinkedIn and the Sweepbase company page.