Bitcoin Post-Quantum (BPQ)BPQ
A December 2018 fork announced at block 555,000 that replaced ECDSA with XMSS hash-based signatures and required holders to move coins with their old keys.
The wiki's angle: BPQ is the 2018 answer to a question Bitcoin still debates in 2026 — what to do with coins whose owners never move them to quantum-safe keys. BPQ's answer was to burn them.[1]
Announcement
On 10 December 2018 the Bitcointalk user pq announced “the fork of the Bitcoin blockchain that will occur on block #555000”, calling Bitcoin Post-Quantum the first Bitcoin fork “with a quantum-safe signature scheme”[1]. The project site says “All bitcoin owners at block height #555000 own the same balance in the Bitcoin Post-Quantum network”[2]. Bitcoin block 555,000 was mined on 22 December 2018[3].
Design
The announcement says BPQ “implements stateful hash-based signature scheme (XMSS W-OTS+)” and that its codebase “is forked from Bitcoin Core 0.16.0 and includes support for SegWit”[1]. The site lists Equihash “with unique parameters (96,3)”, a total supply of 21,000,000 BPQ and a premine of 1,050,000 BPQ[2].
Claiming and burning
To get a balance, holders “must generate a pq-address” and then “enter their old ECDSA keys into the wallet program” to move coins from their old addresses[1]. The announcement says ECDSA support would later be “completely disabled” and that coins not moved to quantum-safe addresses by then “will be burned”[1]. Whether the chain still runs is unknown to this wiki[1].
References
- primarypq, “[ANN] Bitcoin Post-Quantum”, Bitcointalk topic 5082692 (10 Dec 2018) [archived]
- primaryBitcoin Post-Quantum website, bitcoinpq.github.io [archived]
- primarymempool.space, Bitcoin block 555,000 (header time 2018-12-22 23:41:03 UTC) [archived]