Foundry USA, the largest Bitcoin mining pool, has asked its clients to vote on whether it should signal support for BIP-110. The proposal would restrict how much non-payment data Bitcoin transactions can carry. Foundry sent clients a voting link by email and published educational material on the proposal. The pool controls about 23.8% of Bitcoin's total hashrate, so its decision carries real weight in a debate that has divided the network for months.

Voting closes at block 961,632, expected in early August 2026. That block also marks the start of the mandatory signaling period built into the proposal itself, meaning Foundry's poll lands right as the network-wide clock starts ticking.

BIP-110, also called the Reduced Data Temporary Softfork, is a one-year soft fork aimed at Ordinals inscriptions, BRC-20 tokens, Runes, and oversized OP_RETURN payloads. It caps most new transaction outputs at 34 bytes, restores the old 83-byte limit on OP_RETURN outputs, and limits data pushes and witness elements to 256 bytes. Only standard witness versions can be spent while the rules are active.

The goal, according to supporters, is to stop non-monetary data from competing with payments for block space. Existing coins are not affected. UTXOs created before activation stay spendable no matter what wallet software holds them.

The rules are temporary by design. They expire on their own roughly a year after activation, which supporters present as a low-risk way to test the idea without a permanent protocol change.

BIP-110 uses a version-bit signal that miners can include in blocks they mine. If 55% of blocks in any single 2,016-block difficulty period carry that signal, the proposal locks in and activates one period later. That threshold works out to roughly 1,109 blocks out of 2,016, or about 110 blocks a day.

As of mid-July, signaling support sat below 1%. That gap between the required 55% and actual signaling explains why Foundry is now asking clients directly rather than deciding on its own. A pool that size flipping its stance could move the number sharply in a single difficulty window.

Bitcoin Knots, a minority node implementation, ships with BIP-110 support built in. Bitcoin Core, which runs on far more nodes and has the largest developer base, has not endorsed the proposal.

The dispute traces back to 2022, when Ordinals inscriptions first showed developers could embed images, text, and token data directly into Bitcoin transactions. That practice expanded through BRC-20 tokens and later Runes, both of which use transaction space to record token data rather than move bitcoin.

Supporters of BIP-110 argue this data raises storage costs for anyone running a full node, since every node must store and verify every transaction forever. They see it as scope creep away from Bitcoin's purpose as a payment and savings network. Critics counter that Bitcoin has never restricted what users encode in a valid transaction, and doing so now sets a precedent for consensus-level content filtering.

The clash echoes the Blocksize Wars of 2015 to 2017, when the network split over raising the 1 MB block size cap. That fight ended with small blocks winning and big-block advocates forking off to create Bitcoin Cash, then Bitcoin SV a year later. Some in the community worry BIP-110 could produce a similar split if it activates without broad agreement.

Blockstream CEO Adam Back has been one of the most vocal opponents, warning that the proposal could freeze legitimate user funds and that consensus-level intervention could weaken Bitcoin's neutrality toward transactions. He has also questioned whether the proposal has enough real support to justify the risk of a chain split.

Strategy executive chairman Michael Saylor raised a separate concern: that BIP-110 could invalidate transactions that current wallets consider perfectly normal. Bitcoin advocate Samson Mow has criticized both sides, saying the underlying OP_RETURN policy dispute among Bitcoin Core developers was mishandled well before BIP-110 emerged, though he also opposes the proposal on the grounds that protocol changes need wide agreement first.

Adding to the friction, authorship of BIP-110 itself is disputed. The proposal circulated under the pseudonym Dathon Ohm, and Bitcoin developer Greg Maxwell has alleged that Ocean Mining actually wrote it, a claim Dathon Ohm denies.

If signaling stays under 55% through the mandatory window, BIP-110 fails to lock in through the miner fast-track and would need another path to activate, if any. If Foundry's clients push the pool to signal support, and other large pools follow, the threshold becomes reachable within a single difficulty period given how concentrated Bitcoin's hashrate is among a handful of pools.

Either outcome carries a cost. Activation risks a chain split if a meaningful share of node operators and users reject the new rules outright. Rejection leaves the underlying dispute over blockchain data unresolved and likely to resurface under a different proposal number. For now, the decision sits with miners voting through pools like Foundry, not with a single coordinated Bitcoin Core release.