Bitcoin is on the verge of the most important technical battle in years, and most Bitcoin holders don’t even know it’s happening.
Bitcoin is soon on the verge of an inevitable signaling period for a proposal known as BIP 110, expected to happen sometime around block 961,632, days away from this writing. BIP 110 would effectively remove Ordinals inscriptions, BRC-20 tokens, and Runes from new Bitcoin transactions for about a year if it gets locked in. That seems like a nitpicky technical wrangle in a git repository in some corner of the internet. It isn’t. But BIP 110 has attracted the participation of Michael Saylor, Adam Back, Jameson Lopp and some of the most respected names in Bitcoin development, and it has reignited a battle over who gets to determine what Bitcoin is one that hasn’t been as fierce as it was during the Blocksize Wars a decade ago.
Let’s dissect BIP 110, explain why it exists, where the numbers are as miners approach that window and what, if anything, it means for BTC sitting in your wallet.
What BIP 110 Actually Proposes
BIP 110, which is known as the Reduced Data Temporary Softfork, is a Bitcoin Improvement Proposal (BIP) aimed at making embedding non-financial information in a Bitcoin transaction very difficult for roughly one year. A Bitcoin Improvement Proposal is simply a design document. Anyone can write one, and the fact that this one happened to be assigned the number 110 does not imply anything as far as the network is concerned. All it does is say that the document was complete and well-formed enough for cataloging by the repository.
The difference here is more significant than it is elsewhere. On June 25, 2026, BIP 110 was marked Complete in the official bitcoin/bips repository, indicating that the authors believe the written specification is complete. It was assigned a number by the editor who assigned it, Mark Murch Erhardt, who was very clear in public comments that he thought it to be a poorly thought-out and careless proposal. He did anyway, as cataloging a proposal and endorsing it are two jobs. But whether BIP 110 will ever change the way Bitcoin operates is a matter of whether miners, node operators, exchanges and wallet providers will adopt software supporting the change.
The proposal was published using the pseudonym Dathon Ohm, and was drafted originally and technically directed by long time Bitcoin Core contributor Luke Dashjr. It aims to restore incentives, it says, that are misaligned by the use of arbitrary data storage as a supported use case, and to redirect the use of Bitcoin’s block space to its original purpose, moving money.
This happened because of Ordinals, Runes, and a disagreement about OP_RETURN
To grasp the rationale behind this proposal, it’s essential to understand the context of a 2022 technique that allowed users to embed arbitrary information images, text, you name it, into the witness signature data section of the Bitcoin transaction, which Segregated Witness had already introduced for signature data years before. It was there that developer Casey Rodarmor translated that technique into a protocol known as Ordinals, which allowed individuals to attach content straight to an individual satoshi, and trade them like NFTs with no adjustments to Bitcoin consensus code.
Ordinals took off. Shortly after, copycat token standards emerged, starting with BRC-20 and then Rodarmor’s own response, Runes, which he released on the day of the 2024 halving. As each wave came, transactions over $100 were seen briefly at the height of Runes activity, as was real demand for block space. The supporters of this activity noted that the miners were being paid more for this activity than for an equivalent block of plain payments and that fee revenue becomes of increasing importance every four years as the mining subsidy decreases. This, critics Dashjr foremost argued, is not Bitcoin doing its job, it is spam that by chance turned out to be profitable, that crowded out the payments Bitcoin was designed to be, it was spam that silently increased the cost of running a full node for anyone that didn’t want to.
Until October 2025, when Bitcoin Core released version 30, and with it, a move that didn’t have anything to do with consensus rules but that detonated the community nonetheless: the default relay-policy limit for OP_RETURN outputs was increased, from ~80 bytes to 100,000 bytes. Symbolically, this was a Bitcoin local software default, not a network rule that miners could have accepted, oversized OP_RETURN transactions submitted directly to them, limit or no limit, but it was a symbolic default nonetheless. The change is unsafe for the future of Bitcoin, according to Dashjr. A significant portion of node operators reacted by migrating to the alternative client Bitcoin Knots, which maintained the previous, lower limit, and usage of this client started to rise to about 20% of nodes visible in the blockchain.
BIP 110 is the continuation of that battle and is not a local matter of policy, but instead a battle on the consensus layer. While the Core v30 change was an elective and reversible move for anyone running alternative configurations, BIP 110 would ensure that these limitations would be enforced for all Taproot-compatible nodes that implement it, putting an end to the ability to use witness-based methods that Ordinals relies on, not just OP_RETURN itself.
The Seven Rules, in Plain English
Let’s dig out from the jargon and BIP 110 boils down to the following seven consensus rules that will only be active during one deployment window:
- The new transaction output maximum is 34 bytes, except when preceded by OP_RETURN, where the old 83-byte maximum re-applies.
- Most of the data stored on the witness stack, the place where Taproot spending conditions and inscription content sit, will be limited to 256 bytes.
- Once the spending output is created with an unspecified witness or Tapleaf version, it no longer exists and the entire flexible spending space is now open by design.
- The Taproot annex, which is a field that has no current use except for storing additional information, is completely banned.
- Taproot control blocks can only hold 257 bytes, so the number of script paths that can fit into a single Taproot output tree is sufficient for complex but ordinary use, but not the largest experiments.
- Future upgrade opcodes (OP_SUCCESS) become invalid to include.
- The conditional branching instructions, OP_IF and OP_NOTIF, which exist since before Taproot, are disallowed in Taproot.
None of this affects any coins that already exist. All these rules will leave inputs to these transactions that already existed before activation of the new rules as spendable as they are today – existing inscriptions, existing Runes balances as well as every bitcoin already held in a wallet will be as spendable as they are now. Restrictions are only in effect from now on, and then just for the approximately 52,416 blocks that the deployment is active for (about a year). After that, everything old comes back on its own as the old rules are restored.
What the authors provide as justification for the most restrictive of these caps is interesting to consider for a moment, as it is more detailed than the no spam explanation. If the oversized scriptPubKey is stored in the UTXO set, which all full nodes will need to maintain forever on relatively expensive fast storage, it is a perpetual cost for every node operator paid for by one sender’s one-time fee. Large scriptPubKeys have also been used to create so-called poison blocks that can take a very long time for nodes to verify. The 256-byte witness limit is targeted even more specifically at images: today, compression can make a reasonably recognizable image fit into a few hundred bytes, the authors have decided on a threshold specifically small enough to make that impossible while still allowing for a comfortable amount of cryptographic data. The proposal is straightforward, nothing here prevents determined spammers from partitioning their files into smaller parts or turning them into something that looks like it was originally meant to store data, but it does make it more expensive, and it does, as the authors put it, convey the message that data storage is not an intended usage of the base chain.
Why 55 Percent Instead of 95 and Why That’s the Real Fight
Most Bitcoin soft forks, including SegWit and Taproot, function in this manner: a rule, known as BIP 9, requires 95% of blocks in a 2-week window to have a bit set to indicate miner readiness for the change, at which point it will trigger. That is a threshold that is set about as close to unanimous as possible because a permanent consensus change should have something close to it before it affects the entire network.
BIP 110 doesn’t use that threshold. It adopts an adapted deployment, in which only a fraction of blocks, 55% or 1,109 of 2,016, need to be locked up voluntarily in one two-week period. The authors argue that it is a temporary measure and, in their opinion, urgently needed, so there should be a lower standard. However, if that 55% does not occur on its own, the proposal will not simply quietly expire when the deployment of a normal BIP 9 does. Instead, it is going to be in a signaling period, in which no node enforcing BIP 110 will accept a block not signaling for the fork, ensuring that the fork will be locked into the blockchain no later than block 963,648, even if only a minority of miners actually wanted it. Activation of the actual data restrictions follows about two weeks later, at block 965,664.
It’s this mechanism, not the byte limits per se, that critics have been returning to. With forced signaling, a 55% threshold would allow a minority of the network to force a rule change that a majority of the network never actively agreed to in the software for, simply doesn’t accept their blocks unless they conform. It is a user-activated soft fork, which is a legitimate and previously used soft fork breaking tool. Critics label it a form of dragonizing a minority opinion to appear to be a consensus.
Where Signaling Stands as the Window Opens
The answer was virtually nothing for much of this year. Support remained below 50% throughout the spring, and even as of mid-July, it was barely above 1%, with the vast majority of that coming from blocks mined through Ocean, the pool supported by Barefoot Mining and, by the way, Dashjr himself. Ocean mined the first BIP 110-signaling block on March 1, 2026, and had not been seen far from the only centralized source of support since then for several months.
By the last week of July and beginning of August, signaling on public trackers operated by media outlets such as Bitcoin Magazine and independent monitoring sites had started to creep up to the 2-2.6% range as Ocean started to signal by default and a few smaller independent miners followed. That’s a real increase, and worth acknowledging rather than waving away. It’s not even close to 1,109 blocks per period either. So far, none of the four biggest pools in the network – Foundry USA, AntPool, ViaBTC and F2Pool – has pledged to signal. Foundry has instead been conducting its own poll of its customers to determine if the pool should switch, and as of the first days of August, there is no indication that a result has been released yet, but rather one poll that was closing just as the switch was scheduled to take place.
These numbers change daily, so the only way to trust the number is to look at a live tracker, not the number that’s printed at any given moment. The obligatory window will push the effective signal towards 100%, nodes enforcing BIP 110 will simply reject the blocks that don’t signal. I’m not sure if Saylor had a point or not, but when the voluntary threshold reached the mathematically impossible for the current period, a 100% reading is not 100% of the miners.
The Case For and Against BIP 110
Ignore each personality for the moment, and there are actually two more-or-less coherent takes on what block space is for, and why both sides feel they have to protect Bitcoin from the other.
The argument for BIP 110 begins from the premise that Bitcoin is a sound, portable, permissionless currency, and that block space is a shared good that should be used for this purpose first. From this perspective, inscriptions and token protocols are independent of payments, and create additional charges for users who simply wish to send Bitcoin and costs to store data for all nodes, with no request for the data from the nodes whatsoever. The one-year restriction is set to expire by itself rather than being some hard and fast rule, and is intended to be a cooling-off period, time to build something more thought-through without the base layer having to pick up the bill in the interim. The most visible base of support is Ocean Pool and the Bitcoin Knots community, but also some developers who believe that the Core v30 policy change has been in the wrong direction.
The case against BIP 110 is not one, but several, and they are from folks who often don’t agree on much. The thing about fees is that it’s all about precedent: Bitcoin’s rules are supposed to be agnostic about intent. They’re supposed to simply consider whether a fee was paid, and once the network decides that a type of fee-paying transaction is something people don’t like, it doesn’t maintain narrow usage. Adam Back has concentrated more on the mechanism, saying that a low-threshold, mandatory-signaling implementation is a bad way to force an implementation of a change that hasn’t been accepted, and anyone who feels strongly about their opinion can build a fork without forcing anyone else to do so. In fact, Jameson Lopp has characterized this as a danger to two fundamental aspects of Bitcoin that he believes are essential to its value: censorship resistance and predictability: If the network can be censored for subjective content today, it could be censored for other reasons tomorrow. Samson Mow occupies the more complicated middle ground, saying he has real concern about blockchain spam and that the Bitcoin Core way of dealing with the OP_RETURN policy battle was bad, but that BIP 110 is a bad idea because he believes that a change of this magnitude shouldn’t be pushed through a threshold of this size.
Notably, both camps acknowledge that the subtext is true. They are completely at odds over whether altering Bitcoin’s consensus rules is an acceptable method to fix it.
Echoes of the Blocksize Wars
Bitcoin has been here once before, and the two precedents which people constantly reference are in fact in completely opposite directions, that’s why it’s difficult to call.
SegWit itself hasn’t even hit the 95% threshold it requires to activate and only did so in August 2017 after its own signaling stalled far short of the mark. The user-activated soft fork threat to node operators and a critical mass of the economy announcing that they would not accept blocks that did not upgrade broke the logjam. The miners simply followed suit and Bitcoin enabled SegWit without any permanent fork. That’s what BIP 110’s proponents use as evidence that a dedicated minority with sufficient resources can compel change without having to wait for miners to take the lead.
The other precedent is Bitcoin Cash, it cuts the other direction. A group of individuals seeking to pursue an alternative method of scaling forked off from Bitcoin altogether in the same month, with Bitmain, Roger Ver and mining pool ViaBTC all lending their support to the hard-fork. It was not a sideline project. Oh, and no, not in the sense that matters: exchanges continued to have the BTC ticker on the original chain, the market priced Bitcoin Cash at a fraction of Bitcoin’s price within months and a year later, BCH itself forked again, diluting its price for both Bitcoin Cash and Bitcoin SV. It wasn’t just raw mining force, it wasn’t just raw conviction that was lacking to make the market consider a minority chain as Bitcoin.
Compared to those two scenarios, the present-day numbers of BIP 110 seem a lot closer to the second pattern than the first. SegWit’s UASF threat was successful, because it was clearly supported not only by the miners it was putting pressure on, but by exchanges, businesses and node operators far beyond their circle of influence. BIP 110 is in the mandatory window, with low single-digit signalling and no big mining pool supporting it, and no big exchange signing up to enforce it. None of that rules out a chain split if deployment does go to activation, as a small minority of nodes running Knots with the BIP 110 patch could, in principle, end up validating a truly separate chain from everyone else. That does indicate that, in practical terms, the outcome of such a changeover is likely to be a relatively thin and economically limited branch, if it takes place at all and support levels remain unchanged.
What This Actually Means for Your Bitcoin
So unless you’re an everyday holder, or have some complex pre-signed Taproot setups, the actual ramifications are limited here, even if BIP 110 does get activated. Everything else that happens before the activation height is grandfathered, so anything you have today that is spendable remains spendable forever, no matter what chain the market decides to be Bitcoin.
There is one class of people who should take note: those using advanced Taproot setups, such as those created with the Miniscript compiler, which sometimes generate spending conditions that involve OP_IF, or require a script to be placed deeper than seven levels in the tree, both of which BIP 110 would invalidate even for new coins during its window. If you don’t know what that is, chances are you don’t fit the definition. If it does, the proposal includes a 14-day delay between locking in and activation to give such wallets time to transfer funds to a compliant wallet.
For all others, the lesson is more behavioral than technical. Contentious forks are the ones that scammers thrive during: fake claim your forked coins pages, urgent messages about wallets requiring an update prior to some specific date, and copycat sites mimicking official signaling dashboards all tend to flourish in the event of an occasion like this one. Any message that asks you to move money, connect a wallet, or enter a seed phrase due to BIP 110 and that is sent out of the blue is a red flag and should be treated as such, and anything that sounds official should be verified through a source that you had located on your own and not a link sent by someone you don’t know. Running an address through a scanner before sending anything to it doesn’t cost you anything and only takes a few seconds if you ever need a second opinion about an address.
Apart from that, it is never too late to ensure that you aren’t just sitting on an exchange with meaningful amounts of bitcoin during a time of true protocol ambiguity. But while self-custody may not be the solution to the governance issue, it does mean your coins aren’t ensnared in whatever decisions an exchange takes regarding which chain to honor. In our hardware wallets and cold storage guide, we give a step-by-step explanation about how to do that if you haven’t already done it. Or, if you would prefer to see the signalling number move for yourself rather than taking any one article’s word for it, the data is available publicly on any blockchain explorer, and a full walkthrough of how to read a blockchain explorer is available, detailing where to look. If you’re interested in learning more about the mining end of things, how things like Foundry or Ocean even determine what gets included in a block, check out our guide to bitcoin mining software.
What Happens From Here
When you read this, the mandatory signaling window may have already started, and by the time it kicks in in early September, the most important number that determines whether or not it locks in may have been determined. Look at that, but do not assume either way that this is the end of the tale.
BIP 110 reintroduced a question into the fray that Bitcoin has never fully answered: should block space be for whoever pays for it, no questions asked, or does the community have a say in what it’s for? A failed BIP 110 doesn’t answer that question, it simply indicates that this attempt to force an answer lacked the numbers. So, the next time some proposal of this sort in whatever form is offered, it will be facing a community that has just witnessed this one for better or worse. It was always going to be an argument that had to take place. Now BIP 110 just ensured that it happened.
