Bitcoin Core 30 to Increase OP_RETURN Data Limit After Developer Debate Concludes
The developers of Bitcoin Core, the primary open-source software for connecting the blockchain behind the world's largest cryptocurrency, said October's version 30 release will increase the default limit for OP_RETURN data transactions from the current 80 bytes to nearly 4MB, a limit imposed by Bitcoin's block size.
The proposal for the change, which was confirmed in an update on GitHub, had sparked debate within the Bitcoin community. Critics argued that removing the limit could encourage increased embedding of arbitrary data, potentially leading to network spam and a shift from bitcoin's BTC primary function as a financial tool.
This decision to go ahead marks another significant moment in the community's debate about blockchain usage, highlighting persistent tensions between network efficiency, practical use cases and ideological principles.
The OP_RETURN code allows Bitcoin users to include data in transactions. The functionality is conceptually similar to, though technically distinct from, the way Inscriptions embed images and text directly into the blockchain using Ordinals and witness data.
Some argue that adding this transaction data is "arbitrary" and contradicts the original vision for the Bitcoin blockchain as proposed by Satoshi Nakamoto.
The 80-byte limit on OP_RETURN encouraged alternative methods of data storage, some of which caused issues like bloating the unspent transaction output (UTXO) set.
In a detailed GitHub summary and subsequent X post, Bitcoin Core developer Gloria Zhao outlined the reasoning behind the change.
Zhao emphasized the intention to mitigate unintended consequences of the existing limit, noting, 'The primary motivation for this [change] is to correct a mismatch between the harmfulness and standardness of data storage techniques.'
Developer Greg Sanders, who authored the merged pull request, said in GitHub discussions that the removal of the limit 'yields at least two tangible benefits: a cleaner UTXO set and more consistent default behavior.'
Zhao also addressed broader governance issues on her X page, highlighting Bitcoin Core's commitment to transparency and meritocracy.
She stressed the importance of the community's role in maintaining these principles, warning against the risks of social engineering or corporate pressure influencing the software developers' decision-making process.
'If Bitcoin Core's contributors ever abandon these values, e.g., to appease social media or corporate wishes, the community will switch to another node implementation that does it better,' Zhao wrote, urging users to remain vigilant and informed.
Developer Luke Dashjr has consistently opposed easing the limits, labeling the move as potentially harmful. He encouraged users to avoid upgrading to the new version or to adopt alternative node implementations, such as Bitcoin Knots.
The debate mirrors the controversies of 2023, notably around Ordinals and Inscriptions, when users embedded substantial non-financial data, such as images and text, into Bitcoin transactions, prompting similar concerns about blockchain misuse and network congestion.
Despite these concerns, Zhao maintained that attempts to censor transaction types through relay policy are impractical and ineffective against strong economic incentives. Bitcoin Core's approach should remain neutral, reflecting the network's foundational principles of censorship resistance and decentralization, she said.
The Core 30 release will retain manual control options, allowing users to enforce stricter limits through existing command-line parameters. However, these options are now marked as deprecated and will trigger warning messages, indicating potential removal in future updates without a set timeline.

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles


Bloomberg
41 minutes ago
- Bloomberg
Saylor's Strategy Resumes Using Common Shares to Buy Bitcoin
Michael Saylor's Strategy is using common shares again to help finance the crypto treasury firm's purchases of Bitcoin following criticism of the practice by renowned short-seller Jim Chanos. The company formerly known as MicroStrategy Inc. said Monday it acquired $531.9 million of Bitcoin in the seven days ended June 29. It was the first now-almost-weekly purchase announcement since May that noted that the company sold common shares through an at-the-market sales program to fund the buying. It also sold two classes of preferred stock, the Tysons Corner, Virginia-based Strategy said in a US Securities and Exchange Commission filling. It owns about $64 billion in Bitcoin.


Forbes
an hour ago
- Forbes
Quantum Threat: Bitcoin's Fight To Secure Our Digital Future
Will Bitcoin lead the fight against quantum computing to secure our digital future? Leeor Shimron Crypto thrives on cutting-edge technology, but quantum computing could challenge the cryptographic foundations that keep Bitcoin secure. As quantum advancements accelerate, concerns about risks to Bitcoin's blockchain are growing, but the threat extends far beyond crypto. Banking, payments, communications, and other critical industries face similar vulnerabilities, making quantum resilience a global imperative. Could Bitcoin developers, incentivized by a $2 trillion honey pot, lead the charge in pioneering quantum-resistant protections? Let's explore the quantum landscape, assess its impact on Bitcoin and society, and examine the proactive steps being taken to safeguard our digital future. The Quantum Leap: Where We Stand Today Quantum computing is no longer science fiction. Unlike classical computers, which process bits as 0s or 1s, quantum computers use quantum bits, or qubits, which can exist in multiple states simultaneously due to superposition and entanglement. This enables quantum machines to tackle complex problems, like cracking cryptographic codes, at unprecedented speeds. As of mid-2025, quantum computing is still in its adolescence. Google's Willow chip, a 105-qubit processor, made waves in 2024 by reducing error rates, a critical step toward scalable quantum systems. IBM is pushing for a 1,000-qubit chip by 2026 and aims for a million-qubit system by the early 2030s. Other players, like PsiQuantum, Intel, and QuEra Computing, are advancing, with PsiQuantum targeting a million-qubit photonic chip within a similar timeframe. These companies, alongside academic and government initiatives, are driving progress, but we're far from the millions of fault-tolerant qubits needed to break robust cryptographic systems like Bitcoin's. The National Institute of Standards and Technology (NIST) estimates that quantum computers capable of threatening current cryptographic standards won't emerge until the 2030s at the earliest. Significant hurdles in error correction and hardware stability remain, keeping practical, large-scale quantum computers a decade or more away. The Risk to Bitcoin: Cracking the Cryptographic Code Bitcoin's security rests on two cryptographic pillars: the Elliptic Curve Digital Signature Algorithm (ECDSA) for securing wallets and SHA-256 for mining and transaction integrity. These are rock-solid against classical computers, but quantum algorithms like Shor's and Grover's pose theoretical threats. Shor's algorithm could exponentially speed up factoring large numbers and discrete logarithm problems, potentially allowing a quantum computer to derive private keys from public keys. This would compromise Bitcoin wallets, particularly older Pay-to-Public-Key (P2PK) and reused Pay-to-Public-Key-Hash (P2PKH) addresses that expose public keys. A 2022 Deloitte study estimated that 25% of Bitcoin's supply (roughly 4 million BTC, worth over $500 billion at current prices) could be vulnerable. Dormant wallets, like those attributed to Bitcoin's pseudonymous creator Satoshi Nakamoto, are especially at risk due to exposed public keys. Grover's algorithm, while less severe, could halve SHA-256's security strength, potentially giving quantum-equipped miners an edge in solving proof-of-work puzzles. This could centralize mining power, threatening Bitcoin's decentralized ethos, though the network's difficulty adjustment would likely mitigate short-term disruptions. A worst-case 'Q-Day' scenario, where a quantum computer cracks ECDSA en masse, could flood the market with stolen Bitcoin, eroding trust and potentially crashing its price. Experts like Jameson Lopp, CTO of Casa, warn that such an event could be catastrophic, though it remains a remote possibility. Timeframe: A Decade of Breathing Room? Bitcoin has time to prepare. Current quantum computers, like Google's Willow, are nowhere near the estimated 13–300 million qubits needed to crack ECDSA in a practical timeframe. IBM's roadmap suggests a few thousand qubits by 2033, still orders of magnitude short. Most experts peg the quantum threat to Bitcoin as at least a decade away, likely into the 2030s or beyond, given the engineering challenges of building fault-tolerant systems. However, some optimistic projections suggest Bitcoin could face risks within five years if quantum advancements dramatically outpace expectations. This view, driven by claims like Google's Craig Gidney's estimate of breaking RSA with fewer qubits, is a minority opinion and considered unlikely for Bitcoin's stronger ECDSA cryptography. More immediate is the 'harvest now, decrypt later' threat, where adversaries collect encrypted data today, like transaction data from dormant wallets, for future decryption, adding urgency to securing vulnerable addresses. Mitigation Strategies: Building a Quantum-Resistant Bitcoin The Bitcoin community is proactively addressing these risks. Here are the key strategies: Post-Quantum Cryptography (PQC): NIST has been standardizing quantum-resistant algorithms since 2016, with lattice-based cryptography (e.g., Dilithium, Falcon) and hash-based signatures (e.g., SPHINCS+, Lamport) as frontrunners. These rely on mathematical problems quantum computers struggle to solve. NIST has been standardizing quantum-resistant algorithms since 2016, with lattice-based cryptography (e.g., Dilithium, Falcon) and hash-based signatures (e.g., SPHINCS+, Lamport) as frontrunners. These rely on mathematical problems quantum computers struggle to solve. Soft Forks and Hybrid Models: Transitioning Bitcoin to PQC will likely involve a soft fork to introduce quantum-resistant signatures, such as Schnorr-based schemes with enhanced security. Proposals like QuBit, introduced by Bitcoin developer Hunter Beast, aim to integrate post-quantum public keys. Hybrid approaches, combining classical and quantum-resistant cryptography, could ensure backward compatibility during the transition. Transitioning Bitcoin to PQC will likely involve a soft fork to introduce quantum-resistant signatures, such as Schnorr-based schemes with enhanced security. Proposals like QuBit, introduced by Bitcoin developer Hunter Beast, aim to integrate post-quantum public keys. Hybrid approaches, combining classical and quantum-resistant cryptography, could ensure backward compatibility during the transition. Quantum-Resistant Address Migration Protocol (QRAMP): Conceptual proposals like QRAMP encourage users to move funds from vulnerable P2PK and P2PKH addresses to quantum-safe formats. While still in early discussion and lacking formal implementation, such protocols could protect existing funds, though they may increase transaction sizes and require community consensus. Conceptual proposals like QRAMP encourage users to move funds from vulnerable P2PK and P2PKH addresses to quantum-safe formats. While still in early discussion and lacking formal implementation, such protocols could protect existing funds, though they may increase transaction sizes and require community consensus. Best Practices for Users: Bitcoin holders can reduce risks by avoiding address reuse, using multisignature wallets, and storing assets in cold storage. These practices minimize public key exposure, making wallets harder to exploit even if quantum capabilities emerge. Bitcoin holders can reduce risks by avoiding address reuse, using multisignature wallets, and storing assets in cold storage. These practices minimize public key exposure, making wallets harder to exploit even if quantum capabilities emerge. Community Vigilance: Bitcoin's open-source community is its strength. Initiatives like Project Eleven's Q-Day Prize, offering 1 BTC to anyone who can crack an ECC key using Shor's algorithm, are stress-testing vulnerabilities and accelerating PQC adoption. The Bigger Picture: A Threat to Society's Digital Backbone Quantum computing's impact extends far beyond Bitcoin, threatening the cryptographic systems that underpin modern life. Banking relies on RSA and ECC for secure transactions, from wire transfers to credit card payments. A quantum breakthrough could expose bank accounts and financial systems to fraud, potentially disrupting global markets. Payment networks like Visa and Swift, which process trillions annually, depend on similar cryptography, and a 'Q-Day' breach could halt transactions or erode consumer trust. Communications platforms, such as TLS/SSL for secure browsing, VPNs, and encrypted messaging apps like Signal, face vulnerabilities, risking data breaches or surveillance on an unprecedented scale. Critical infrastructure, including healthcare systems storing sensitive patient data and government networks securing classified information, is equally at risk. The scale of the threat is staggering. The 2023 EY Quantum Approach to Cybersecurity report, citing a Forrester study, estimates a 50%-70% chance that quantum computers could break current cryptographic systems within 5 to 30 years, implying that a majority of global digital transactions relying on asymmetric cryptography (e.g., RSA, ECC) are vulnerable. National Security Memorandum 10 mandates U.S. federal systems transition to PQC by 2035, a timeline Bitcoin developers are likely to align with. Unlike centralized systems, which face bureaucratic delays, Bitcoin's decentralized governance and $2 trillion market cap create unique incentives. This massive 'honey pot' motivates developers to pioneer quantum-resistant solutions, potentially setting a standard for other industries. Projects like QuBit and QRL demonstrate that crypto can lead the way, leveraging open-source collaboration to deploy PQC faster than banks or governments. For investors, quantum risks are on the radar. BlackRock's 2025 filing for its Bitcoin ETF (IBIT) flagged quantum computing as a long-term concern, signaling institutional awareness. Bitcoin's adaptability gives it an edge, but transitioning to PQC could spark debates over block size, transaction throughput, and network upgrades—issues that have historically divided the community. The Path Forward: Preparedness, Not Panic Bitcoin's resilience lies in its ability to evolve. The Y2K crisis showed that tech systems can adapt to existential threats with coordinated effort, and Bitcoin's quantum challenge is no different. The community has a window, likely 10–15 years or even longer, to implement quantum-resistant solutions. Developers are laying the groundwork, and users can take immediate steps to secure assets. The real risk isn't quantum computing but complacency. Bitcoin developers, spurred by a $2 trillion incentive, are uniquely positioned to lead the charge in quantum-resistant cryptography, potentially creating best-in-class protections that banks, payment processors, and governments could emulate. As David Carvalho of Naoris Protocol noted, 'Satoshi gave the world a new monetary system but never said it couldn't evolve.' By embracing PQC, fostering consensus, and staying vigilant, Bitcoin can weather the quantum storm and set a precedent for a quantum-safe digital world.


Gizmodo
an hour ago
- Gizmodo
Why You Should Care About This War Over the Future of Money
The crypto world is buzzing. If you ask a true believer, they'll say this is just the beginning of a financial revolution. Ask a skeptic, and they'll swear we're watching a bubble inflate in real time, one that could pop at any second. This entire debate is now playing out in a public showdown between two of the biggest names in finance. Michael Saylor and Jim Chanos are two men with very different visions of the future, and they're now in open combat on X (formerly Twitter). Saylor, the billionaire co-founder and executive chairman of MicroStrategy (now rebranded as Strategy), has spent the last few years transforming his company from a sleepy enterprise software firm into a Bitcoin holding vehicle. Strategy now holds over 592,345 Bitcoins, worth tens of billions of dollars, according to And it's not stopping there. Saylor believes Bitcoin isn't just a digital asset, but a form of monetary energy that will replace cash, gold, and maybe even government bonds. On the other side is Jim Chanos, the legendary short seller who made his name betting against Enron and winning. He's now warning that MicroStrategy's entire Bitcoin pivot is built on hype, not fundamentals. The two are clashing over Saylor's latest move: the launch of new digital securities — tickers like $STRK, $STRF, and $STRD — that Saylor says are 'driving the digital transformation of the credit markets.' These are blockchain-based financial instruments tied to MicroStrategy's Bitcoin holdings, and they're being marketed as next-generation alternatives to traditional debt. '$MSTR is driving the digital transformation of the credit markets,' Saylor declared on X, linking to promotional material about these new securities. Chanos fired back immediately, dismissing the move as a distraction. 'As much as he wants to push the $MSTR preferred narrative, they represent less than 3% of the current $MSTR EV ($120B).' As much as he wants to push the $MSTR preferred narrative, they represent less than 3% of the current $MSTR EV($120B). — James Chanos (@RealJimChanos) June 27, 2025So, what's really happening here? Saylor's company, Strategy, is the world's most aggressive Bitcoin treasury company. This simply means it's a public company that has decided to hold Bitcoin on its balance sheet instead of traditional cash reserves. It's like if Apple decided to hold Bitcoin instead of dollars on its balance sheet. Its new digital securities, like $STRK, $STRF, and $STRD, act like corporate bonds or preferred stock. But instead of being issued and tracked through Wall Street, they exist on the blockchain. This makes them programmable, instantly traceable, and theoretically more efficient to trade. Saylor believes this is the future of corporate finance: a world where companies raise money and pay investors directly using Bitcoin and blockchain 'rails,' cutting out the big banks and other middlemen. This vision is the core promise of DeFi, or decentralized finance, an attempt to rebuild the entire financial system using open-source code instead of gatekeepers. Chanos, on the other hand, sees it as a distraction, a shiny new crypto toy that doesn't move the needle. His argument is that these new digital assets are just a sideshow, representing a tiny fraction of Strategy's total enterprise value (EV) and doing nothing to justify its staggering $100 billion market capitalization as of June 27. He believes the company is just a glorified Bitcoin fund that is trading at a huge premium to the value of the Bitcoin it actually holds, a premium propped up by hype and a cult-like belief in Saylor's vision. This fight is about much more than one company. It's a battle over the future of money. If Saylor is right, we could be at the dawn of a new era where more companies abandon the dollar in favor of Bitcoin and rebuild Wall Street from scratch. But if Chanos is right, it's all smoke and mirrors, and Strategy is ground zero for the next great crypto collapse. Saylor is betting the future of his company and his fortune on Bitcoin. Chanos is betting that future doesn't exist. One of them will be spectacularly wrong.