BIP-110 UASF: How many blocks signal bit 4 in the final difficulty period before mandatory signaling?
35,374 Vol.in 1 month (Aug-15-2026 12:00:00 PM UTC)
Outcome
% Chance
Show chart
21+ blocks (1.04%)
$7,311 Vol.
78.0%
Show chart
26+ blocks (1.29%)
$18,459 Vol.
42.0%
Show chart
16+ blocks (0.79%)
$9,604 Vol.
38.0%
DescriptionBitcoin's spam war has gone consensus-level. BIP-110 ("Reduced Data Temporary Softfork") is a UASF that would re-limit arbitrary on-chain data; miners back it by setting bit 4 in the block header version. Core has not endorsed it, and Adam Back and Jameson Lopp warn the parameters risk a chain split. Signaling is near-zero: period 472 = 16 blocks, 473 = 9, 474 = 20, with 475 tracking ~0.76%. Ocean mines nearly all signaling blocks; F2Pool has refused. Period 476 (blocks 959,616-961,631) is the last voluntary period before mandatory signaling at block 961,632 (~Aug 7-8, 2026).
- Each outcome resolves YES if bit-4 signaling blocks in period 476 reach its threshold, and NO if below it.
- 1. Specificity: Count is over the 2,016 blocks 959,616-961,631 inclusive on the most-work Bitcoin mainnet chain. A block counts if (version & 0xE0000000) == 0x20000000 AND (version & 0x10) != 0. Thresholds: 16 = 0.79%, 21 = 1.04%, 26 = 1.29%. Cited history is monitor-derived; this bitmask governs resolution.
- 2. Exclusion: Signaling in any other period (475, 477) does not count. Pool or developer statements, media "miner support"/hashrate-share figures (often quoted at 2-3%), Knots node share, and non-mainnet chains do not count. Lock-in or activation is NOT required.
- 3. Source Hierarchy: Raw block header version from mempool.space is primary, verifiable on any Core node via getblock. bip110.org/monitor is secondary, bip110monitor.com tertiary; neither overrides raw chain data.
- 4. Timing: Measurement is fixed by block height, not clock time (UTC). Resolution occurs once block 961,631 has 6 confirmations (projected Aug 7-8, 2026). An outcome resolves early once mathematically determined, provided the deciding block has 6 confirmations. Backstop: if block 961,631 is unconfirmed by 2026-09-15, outcomes resolve on confirmed in-range blocks only, counting unmined blocks as non-signaling.
- 5. Reorg Rule: If a reorg changes the count, the most-work chain 6 blocks after 961,631 is authoritative.