Adam Back, CEO of Blockstream and one of the few people actually cited in the Bitcoin whitepaper, is sounding the alarm on BIP-110. The proposal, which would restrict arbitrary data storage in Bitcoin transactions, is barreling toward its mandatory enforcement block height with almost nobody on board.

The two possible outcomes, according to Back: it either triggers a chain split around August 7th, or it simply fails to activate.

What BIP-110 actually does

BIP-110 wants to impose strict limits on non-monetary data, capping OP_RETURN outputs at 83 bytes and restricting data pushes to 256 bytes. It would make life significantly harder for protocols like Ordinals and Runes, which use Bitcoin’s block space to store images, tokens, and other data that purists consider “spam.”

The proposal originally surfaced as BIP-444 in late 2025 before being renumbered. It’s structured as a one-year soft fork, meaning its restrictions would be temporary. But the mechanism it uses to get there, a User Activated Soft Fork (UASF), is where things get dicey.

UASFs work by having nodes enforce new rules regardless of whether miners agree. The idea gained credibility during the 2017 SegWit activation battle. But there’s a crucial difference between 2017 and now: back then, there was broad community support for the change. BIP-110 doesn’t have that luxury.

The numbers tell a brutal story

As of March 2026, BIP-110 had gathered roughly 2.4-4.5% support from network nodes. Most of that comes from Bitcoin Knots, an alternative node implementation maintained by Luke Dashjr, who has been one of the most vocal advocates for limiting non-monetary data on Bitcoin.

No major mining pools have signaled support for the proposal. Zero.

The mandatory enforcement kicks in at block height 961,632, projected to arrive around August 7, 2026, at roughly 17:59 UTC. When that block height hits, any node running BIP-110-compatible software will begin rejecting blocks that violate the new rules.

Back has described BIP-110 as an “intentional literal downgrade” that disrupts Bitcoin’s userspace and freezes UTXOs. That last point is particularly concerning: certain existing transaction outputs could become unspendable under the new rules, effectively locking up people’s Bitcoin.

Jameson Lopp, another well-known Bitcoin developer, has echoed these concerns, arguing that the proposal could break compatibility with existing protocols and scripts.

The governance problem underneath

The UASF activation path BIP-110 chose requires a lower support threshold to trigger enforcement. The philosophy behind it is that users, not miners, are the ultimate arbiters of Bitcoin’s rules. In practice, trying to force a contentious change through a UASF with less than 5% support is less “grassroots revolution” and more “shouting into the void.”

The proposal remains in draft status on GitHub, with updates continuing through March 2026.

What this means for investors

With no mining pool support and single-digit node adoption, the math simply doesn’t work for a successful soft fork. But if a small group of nodes fork themselves off the main chain, it could create a brief period of confusion and volatility.

Investors should watch two metrics as August approaches. First, whether any mining pools begin signaling support for BIP-110, which would change the calculus entirely. Second, whether the proposal’s backers choose to modify the activation parameters or push forward regardless.

The Ordinals and Runes ecosystem, which BIP-110 directly targets, has become a meaningful source of miner revenue through transaction fees. The fact that miners have shown zero interest in BIP-110 suggests they’re quite happy with the current fee revenue those protocols generate.