On September 3, 2013, Sergio Demian Lerner published “A New Mystery about Satoshi Hidden in the Bitcoin Block-Chain,” revealing a second, independent fingerprint in Satoshi’s early mining — beyond the ExtraNonce slope analysis he had published four and a half months earlier.
The discovery
Lerner analyzed the least significant byte (LSB) of nonce values from the genesis block to block 36,288. In a standard mining implementation, nonce bytes should be uniformly distributed. Instead, Satoshi’s blocks showed a striking non-random pattern. The counts Lerner listed for the blocks up to 20,000 begin:
- Values 0–9: 247–324 occurrences each
- Values 10–18: only 2–6 each — a critical gap
- Values 19–58: high again, from 138 at 19 to 201 at 58
- Values 59–255: low from there on (7 at 59)
The pattern was exclusive to unspent coinbases (Satoshi’s blocks) and absent from blocks mined by other early participants.
Significance
This LSB restriction to approximately 50 out of 256 possible values ([0..9] ∪ [19..58]) was a completely independent line of evidence from the ExtraNonce analysis. It proved the dominant miner used custom software that partitioned the nonce search space — assigning different LSB ranges to different threads or processes to avoid duplicate work.
Initial hypotheses
Lerner proposed four explanations: a parsing error, specialized hardware using gray codes, a SHA-2 vulnerability, or an intentional fingerprint. Community member “Eyal0” quickly proposed an answer that Lerner first judged right: Satoshi had access to dozens of machines, and to avoid checking the same nonce twice he gave each a different ID, stamped in the LSB of the nonce.
Follow-up (September 4, 2013)
In “Satoshi’s Machine,” Lerner confirmed the LSB-ExtraNonce connection and determined that the restricted nonce range made Satoshi’s computer appear approximately 4.3 times faster than it really was — consistent with a single computer running at least four threads, or four computers under one owner, rather than dozens of machines.
Sergio Demian Lerner (Bitslog blog post, September 4, 2013)We’re living in a LOST movie: each time it looks a mystery is solved, another one appears.
In April 2019 Lerner named the pattern “Patoshi” and calculated how unlikely this LSB restriction is under ordinary mining (the 2019 Patoshi-naming entry).
Lerner returned to the hardware question at length in the 2020 Patoshi mining-machine analysis, whose re-mining simulation confirmed the single-CPU, five-thread configuration that the nonce-partitioning pattern discovered here implies.
