Ripple said on Aug. 25 that its RLUSD stablecoin crossed $2 billion in market capitalization during the previous week, less than two years after its December 2024 launch.

Close to $1 billion of the circulating supply had been issued on the XRP Ledger, according to Ripple’s official statement. CoinGecko subsequently placed RLUSD’s market capitalization at approximately $2.11 billion, based on a circulating supply of about 2.1 billion tokens.

Because RLUSD seeks to maintain a $1 price, its market capitalization closely tracks its circulating token supply. The milestone therefore reflects additional issuance rather than price appreciation.

StarkWare researcher Avihu Levy says he has successfully carried out an experimental, quantum-resistant Bitcoin transaction directly on the Bitcoin mainnet—an onchain test intended to validate a proposal originally outlined earlier this year. StarkWare described the transfer as the first transaction of its kind, using Levy’s “Quantum Safe Bitcoin” (QSB) scheme.

According to StarkWare, the transaction was confirmed Wednesday in Bitcoin block 964,199. Mempool data shows the spend used a 10,000-satoshi output protected by Levy’s QSB authorization, while MARA Pool mined the block after receiving the transaction via its Slipstream service. The test is notable not because it changed Bitcoin’s consensus rules, but because it demonstrates a quantum-resistant spending construction that can be executed within existing Bitcoin infrastructure.

Key takeaways

• StarkWare reports an onchain QSB transaction was confirmed in Bitcoin block 964,199, marking a move from theory to a mainnet demonstration.
• QSB is designed to be quantum-resistant without requiring a Bitcoin protocol upgrade, relying instead on transaction-level cryptographic construction.
• The computation required to create QSB transactions remains expensive, with StarkWare estimating the final test cost in the low hundreds of dollars (around $150–$200).
• QSB transactions are treated as nonstandard by Bitcoin Core relay policies, meaning typical nodes may not propagate them automatically.
• Bitcoin developers are already considering protocol-level changes, including proposals such as BIP-360, that aim to reduce quantum exposure for specific spend paths.

From proposal to a confirmed mainnet spend

Levy’s QSB work combines two cryptographic ideas: hash-based one-time signatures and computational searches that bind an authorization to a specific transaction. StarkWare’s research framing is that this construction should prevent forgery even if a future quantum computer undermines the elliptic-curve cryptography used by Bitcoin today.

The onchain test matters because it shows that this specific quantum-resistant mechanism can be expressed under Bitcoin’s current consensus rules—at least in a way that results in a valid, confirmable spend. StarkWare said the demonstration was carried out without a protocol change, moving the project from “paper and code” into a working mainnet transaction.

Levy’s paper and associated code repository describe QSB in more detail, including how the one-time signature and transaction-bound authorization work together to create the security target against quantum-enabled forgery.

Cost and practicality: compute-heavy by design

Quantum-resistant cryptography usually involves a tradeoff: stronger security against future threats often comes with higher computational and operational costs. StarkWare’s spokesperson Nathan Jeffay told Cointelegraph that completing the tested transaction cost “low hundreds of dollars,” estimating roughly $150 to $200. StarkWare also said the overall process involved hours of computation.

This echoes earlier expectations around QSB’s resource intensity. In April, Levy introduced QSB and estimated then that generating a transaction could require between $75 and $150 in GPU computation. In the current test, StarkWare’s final estimate suggests the method is feasible for experimentation, but far from something that can scale as a default spending option for everyday users.

Levy’s approach has also been framed as a “last-resort measure” rather than a full replacement for protocol-level improvements. That distinction is important for readers trying to understand what QSB is solving: not immediate mass adoption, but a credible bridge for security concerns while Bitcoin’s broader roadmap for post-quantum resilience is still being discussed.

Why nodes may not relay QSB transactions by default

Beyond cost, QSB faces a practical integration barrier: Bitcoin Core’s default relay policy. Levy’s repository classifies QSB transactions as nonstandard, and StarkWare said this means ordinary nodes would not automatically propagate them before confirmation.

In other words, a QSB transaction may not travel through the usual network “gossip” path. For the confirmed test, the transaction was submitted through MARA’s Slipstream service so it could reach miners despite its nonstandard status.

This is a reminder that even when a cryptographic scheme is valid under consensus, network policy still shapes real-world usability. Until relay behavior changes—or until spending routes are standardized—quantum-resistant transactions may remain mainly the domain of researchers and specialized operators.

Protocol upgrades are still on the table

QSB’s transaction-level strategy also raises a broader question: what happens as Bitcoin evolves toward quantum readiness at the protocol layer?

In earlier reporting, Google researchers estimated that if a sufficiently capable quantum computer emerged, it could potentially derive a Bitcoin private key nine to 12 minutes after its corresponding public key becomes visible—creating a window where an attacker might replace a pending transaction. The implication is that certain spending constructions may be more vulnerable than others once quantum capabilities arrive.

Levy introduced QSB with the notion that it does not require a network-wide upgrade, but still provides a safety net. StarkWare’s Eli Ben-Sasson indicated in comments to Cointelegraph that he expects a soft fork to eventually happen, describing QSB as a transitional protection while protocol-level safeguards are developed.

Bitcoin developers are separately weighing proposals that target specific spend paths. One example mentioned by StarkWare is BIP-360, a proposed soft fork that would introduce a Pay-to-Merkle-Root output type while removing Taproot’s quantum-vulnerable key-path spend. This kind of proposal differs from QSB by aiming to reduce exposure directly through changes to how certain outputs are constructed and spent, rather than relying on transaction-level workarounds.

Notably, QSB in this test is presented as a validation that one quantum-resistant approach can be executed without a protocol change. The next step for the community will be whether standardized relay and broader compatibility can be achieved, and how that compares with the security and complexity tradeoffs of protocol-level soft forks.

What to watch next

For now, the key uncertainty is scalability and integration: whether future QSB tests can lower compute cost, and whether changes to Bitcoin relay standards—or eventual soft fork designs like BIP-360—will reduce the friction that currently makes these transactions nonstandard. Readers should also look for more mainnet demonstrations that clarify how reliably the method can be used across different mining and submission workflows.

Coinbase and Better Mortgage have made a Bitcoin-backed mortgage product generally available to qualified US homebuyers, allowing them to secure a down payment loan without selling their BTC.

Bitcoin-backed home loans use a two-loan structure

Better Mortgage and Coinbase announced the rollout on Aug. 26, opening the product after testing it with a limited group of borrowers. Better originates and services the loans, while Coinbase provides the infrastructure used to transfer and hold the Bitcoin collateral.

Rather than creating one mortgage secured partly by a home and partly by cryptocurrency, the companies have divided the financing into two loans. One is a standard first-lien mortgage designed to meet Fannie Mae’s conforming guidelines. A separate loan, secured by the borrower’s Bitcoin, supplies the cash needed for the down payment.

Both loans carry the same interest rate and amortization period, according to the Coinbase Help Center. Borrowers make one combined monthly payment instead of servicing the mortgage and down payment loan separately.

To qualify, applicants must pledge BTC worth at least 250% of the loan down payment. Someone seeking $100,000 for a down payment would therefore need to provide Bitcoin valued at no less than $250,000 when the collateral is posted.

Following approval by Better, the borrower authorizes the transfer of the required Bitcoin from a verified Coinbase account to Better’s custodial account on Coinbase Prime. Better controls the collateral during the life of the financing, and the borrower cannot trade or withdraw the pledged coins.

The company returns the full amount of pledged BTC after the mortgage is repaid or refinanced, subject to the final loan terms. Repaying the down payment loan separately does not appear to release the collateral early because Coinbase says Better holds it until the entire mortgage is paid off or refinanced.

Bitcoin price declines do not cause margin calls

Unlike many crypto-backed loans, the Better product does not require borrowers to add collateral merely because Bitcoin loses value. Coinbase states that day-to-day price movements will not change the mortgage terms or produce a margin call.

Payment failures carry a different consequence. Under the product terms, Better can liquidate the pledged Bitcoin once a borrower becomes 60 days delinquent on the loan payments.

A borrower therefore retains exposure to possible Bitcoin gains but also places the pledged holdings at risk if payments stop. The two-loan structure also means the homebuyer takes on debt for the down payment instead of contributing cash at closing.

Selling Bitcoin to fund a home purchase can create US tax consequences because the Internal Revenue Service treats digital assets as property. A taxable gain or loss generally arises when a holder sells or otherwise disposes of cryptocurrency, according to IRS guidance. Pledging BTC as collateral does not involve an immediate sale, although any later liquidation could have tax consequences depending on the borrower’s circumstances.

Applicants must be US residents, maintain a verified Coinbase account in good standing, and hold enough Bitcoin to meet the collateral requirement. Better still examines credit, income, and other financial information under its underwriting policies, meaning ownership of sufficient BTC does not guarantee approval.

Coinbase does not originate the mortgage or make lending decisions. Better handles applications, underwriting, closing, escrow matters, and payment servicing, while Coinbase manages services related to the customer’s account and the transfer of collateral.

Coinbase One members can receive up to $10,000

Coinbase One members approved for eligible Better financing can receive a rebate equal to 1% of the mortgage value, capped at $10,000. Better pays the rebate as a lender credit against closing costs and records it on the borrower’s closing disclosure.

The companies have extended the offer beyond Bitcoin-backed mortgages to Better’s standard mortgages, home equity lines of credit and refinancing products. Eligible Coinbase One members have been able to apply for the expanded offer since Aug. 12.

Early demand supplied one reason for moving beyond the controlled launch. Better said, 76% of people on the June waitlist were already Coinbase One members, while 60% planned to buy a home within six months. Responses indicated more than $260 million in projected loan volume before general availability.

Ziggy Jonsson, Better Mortgage’s chief technology officer, linked the product to changes in how some younger Americans hold their wealth.

“By allowing Coinbase One members to pledge crypto as collateral without selling their holdings, we’re opening a new path toward homeownership for a generation of borrowers whose wealth increasingly lives onchain,” Jonsson said.

The present product supports Bitcoin, according to Coinbase’s current eligibility page. Earlier plans had referred to both BTC and the USDC stablecoin, but the current instructions specify that applicants need enough Bitcoin in their Coinbase account to cover the required collateral.

As previously reported by crypto.news, Better, and Coinbase disclosed the planned product in March. Details available at the time showed that buyers would receive a traditional home loan alongside a separate crypto-secured down payment loan, although the complete eligibility and collateral conditions had not yet been released.

US mortgage rules begin recognizing crypto holdings

In June, the companies funded the first Fannie Mae-backed US mortgage using Bitcoin as collateral. The loan went to a couple in Ann Arbor, Michigan, who pledged BTC rather than selling it to raise the down payment.

Better estimated at about $250 million in potential lending volume from the waitlist at the time. The completed transaction served as an early test before the product became available to qualified borrowers across the company’s market.

US housing policy had already begun making room for digital assets. In June 2025, the Federal Housing Finance Agency directed Fannie Mae and Freddie Mac to prepare proposals for considering cryptocurrency in single-family mortgage risk assessments without first converting the assets into dollars.

The directive limited consideration to holdings that could be verified through US-regulated centralized exchanges. It also instructed the two government-sponsored enterprises to account for cryptocurrency volatility and develop risk controls before submitting board-approved plans to the FHFA.

Newrez took a separate step in January 2026, announcing that it would begin considering certain cryptocurrency holdings when reviewing mortgage applications in February. Its policy covered applications for purchases and refinancing, adding another route for borrowers whose assets include digital currencies.

High housing costs provide the financial setting for the new products. Data from the US Census Bureau and Department of Housing and Urban Development, compiled by the Federal Reserve Bank of St. Louis, placed the median sales price of a new US home at about $400,000 in 2026. Better also said that high borrowing costs, expensive homes, and limited inventory pushed the median age of a first-time US buyer to 40 in 2025.

Major U.S. and international banks are reconsidering stablecoins as crypto companies and technology groups expand into payments, according to an Aug. 26 Wall Street Journal report.

The shift remains preliminary. JPMorgan told the publication that it has no current plan to issue a stablecoin, while several reported consortium projects have not announced launch dates, product structures or regulatory approvals.

JPMorgan evaluated a stablecoin without approving one

JPMorgan recently discussed whether to issue its own stablecoin, the Journal reported, citing people familiar with the matter. The bank has not started developing an active product.

“While we have no plans to issue a stablecoin,” a JPMorgan spokeswoman said, the bank could review its options as customer demand and regulations evolve.

The statement leaves open future participation but does not confirm that JPMorgan will issue a token. Chief Executive Jamie Dimon previously said the bank would become more involved with stablecoins to understand their role and compete with financial-technology companies.

JPMorgan already operates JPM Coin through its Kinexys blockchain platform. JPM Coin is a deposit token representing a customer’s claim against JPMorgan, rather than an independently issued payment stablecoin backed by a separate reserve portfolio.

Global banks reportedly consider a shared stablecoin

More than a dozen financial institutions, including Bank of America, Wells Fargo and Santander, are reportedly advancing a global stablecoin venture. The group would initially focus on a U.S. dollar token before potentially adding euros and other Group of Seven currencies.

The participants have not publicly released the project’s complete membership, governance model, backing arrangements or timetable. The reported plan should therefore be treated as under consideration rather than an approved launch.

Large banks are also developing tokenized-deposit networks. As previously reported, JPMorgan and several rivals backed a shared network designed to keep customer money inside the commercial banking system.

A tokenized deposit remains a liability of the issuing bank and may retain access to existing banking protections. A stablecoin normally circulates as a separate payment instrument backed by reserves, with legal protections depending on the issuer and governing framework.

BankChain brings community banks into blockchain payments

Separately, 39 state bankers associations announced the formation of BankChain Alliance on Aug. 25. The associations represent thousands of U.S. banks, although individual member banks have not necessarily committed to joining the planned network.

BankChain’s official announcement says the platform will be owned, designed and governed by the banking industry. It could support stablecoins, tokenized deposits, smart payments and automated settlement.

BankChain described its planned network as “secure, regulated” infrastructure, but it has not selected a technology partner or launched an operating product.

The alliance is targeting 2027 and intends to make its network interoperable with other payment systems. Its final technology, funding, membership and regulatory structure remain undisclosed.

The project gives smaller and regional banks a possible shared route into blockchain payments. Building a common system could reduce the cost of developing separate infrastructure while preserving bank control over customer relationships and deposits.

Stablecoin rules will determine what banks launch

The GENIUS Act created a U.S. framework for payment stablecoin issuers, but several implementing rules remain unfinished. As crypto.news reported, federal agencies missed the law’s initial rulemaking deadline.

The Office of the Comptroller of the Currency expects to finalize its stablecoin rule by November 2026, according to the agency’s current schedule. The final requirements will shape reserve management, disclosures, redemptions and bank participation.

Banks must also decide whether stablecoins provide enough commercial value beyond tokenized deposits and existing instant-payment systems. Crypto-native stablecoins offer wider blockchain distribution, while deposit tokens keep money within a bank’s balance sheet and regulatory perimeter.

No verified market reaction can be attributed specifically to the Journal report. The next firm developments would include named consortium members, regulatory applications, technology selections and confirmed launch schedules.

StarkWare researcher Avihu Levy says he has successfully completed what the company describes as the first quantum-resistant Bitcoin transaction on the mainnet—an onchain test of Levy’s Quantum Safe Bitcoin (QSB) approach.

According to StarkWare, the transaction was confirmed Wednesday in Bitcoin block 964,199, and onchain data indicates it spent a 10,000-satoshi output protected using QSB. Block propagation for the test relied on MARA Pool’s Slipstream service, reflecting that the experiment did not follow Bitcoin Core’s default transaction relay rules.

Key takeaways

• First mainnet demonstration: StarkWare reports QSB was confirmed in Bitcoin block 964,199, moving Levy’s April proposal from concept to live spending.
• No consensus upgrade required: StarkWare says the test was compatible with Bitcoin’s existing consensus rules, without changing the protocol.
• Higher compute costs: StarkWare estimates the transaction required “low hundreds of dollars,” with computation taking hours.
• Relay constraints: QSB transactions are treated as nonstandard under Bitcoin Core default policies, so they required direct submission via Slipstream rather than normal peer-to-peer propagation.
• Stops short of a network-wide fix: QSB hardens individual spending, while broader protocol proposals (including BIP-360) aim to reduce quantum exposure more systematically.

QSB reaches mainnet: hash-based signatures plus transaction-bound authorization

Levy’s QSB combines two ideas intended to counter scenarios where quantum computers undermine Bitcoin’s elliptic-curve cryptography. In StarkWare’s description of the scheme, QSB uses hash-based one-time signatures and pairs authorization to a specific transaction through computational searches.

The goal is to prevent forgery even if a quantum computer eventually breaks the cryptographic primitives underpinning Bitcoin’s typical key-path spending. Rather than replacing Bitcoin’s cryptography across the network, QSB is designed as a construction for individual transactions—effectively a “last-resort” safety net that can be used when quantum risk becomes more urgent.

StarkWare points to Levy’s published paper and code repository as the technical basis for the method, with the repository detailing how transaction-specific authorization is bound into the spending conditions.

What changed vs. earlier proposals—and what remains theoretical

The QSB test is best understood against earlier academic and research milestones. In March, researchers at Google estimated that a sufficiently capable quantum computer could theoretically derive a Bitcoin private key within minutes after an attacker learns the corresponding public key from a pending transaction, potentially enabling key replacement during the confirmation window.

In April, Levy introduced QSB in response to that kind of threat model, describing the approach as costly and intended for rare use rather than routine replacement of existing defenses.

StarkWare’s Wednesday mainnet confirmation therefore marks an important shift: it demonstrates that a quantum-resistant spending construction can be executed under Bitcoin’s current consensus rules, at least in this controlled experiment. That matters for investors and builders because it suggests a path for incremental, transaction-level hardening while longer-term protocol changes are debated and implemented.

Cost, computation time, and the reality of running it on Bitcoin

While the concept is aimed at quantum resistance, the test also highlights the practical trade-off: compute intensity. StarkWare previously estimated that generating a QSB transaction would require between $75 and $150 in GPU computation, framing it as a fallback option rather than a universal tool.

For the confirmed mainnet run, StarkWare’s spokesperson Nathan Jeffay told Cointelegraph that the total cost landed in the “low hundreds of dollars,” estimating around $150 to $200. StarkWare’s release also said the process took hours of computation.

That pricing and time profile is critical context for market participants: even if QSB can be made to work without a protocol update, its cost structure will likely limit how often it can be used in practice until either hardware efficiency improves or alternative constructions reduce compute requirements.

Why it required a special submission path: nonstandard relay policies

Beyond cost, StarkWare’s testing approach underscores another bottleneck: Bitcoin nodes may not relay QSB transactions in the same way they handle standard transfers.

Levy’s repository classifies QSB transactions as nonstandard under Bitcoin Core’s default relay policies. StarkWare says this means ordinary nodes would not propagate the transaction before confirmation, so the test needed to be submitted directly through MARA’s Slipstream service.

In practical terms, that implies a two-stage readiness problem. Even if the spending is valid under consensus rules, the transaction’s ability to spread through the network—at least by default—can affect timing, reliability, and user experience. Observing whether QSB can become easier to submit, relay, or include under broader conditions will likely be one of the next milestones builders watch.

QSB as a bridge while protocol-level protection advances

StarkWare’s leadership also positions QSB as incomplete by design. The method applies to individual transactions rather than upgrading cryptography throughout the Bitcoin network. StarkWare CEO Eli Ben-Sasson said, “A soft fork should happen, and I believe it will,” framing QSB as a safety net while protocol-level protections are developed.

That broader effort is already reflected in public proposals discussed in the Bitcoin ecosystem. One example mentioned by StarkWare is BIP-360, a proposed soft fork that would introduce a Pay-to-Merkle-Root output type while removing Taproot’s quantum-vulnerable key-path spend.

The tension here is straightforward: QSB can demonstrate feasibility today, but protocol changes aim to make quantum-resistant spending practical at scale—potentially without requiring specialized submission routes or heavy computation per transaction.

For traders and long-term holders, this also changes how to think about “quantum readiness.” Instead of a single all-or-nothing moment, the landscape appears to be moving toward layered defenses: transaction-level constructions that prove the mechanics, paired with eventual consensus changes that reduce exposure and simplify use.

Going forward, the key question is whether QSB tests like this can be repeated reliably across different infrastructure and whether future improvements—or soft fork proposals such as BIP-360—make quantum-resistant spending cheaper, easier to relay, and more broadly usable without specialized services.