Bitcoin only — follows ONE UTXO's continuity, branches on clean splits, stops and flags on merges
Forward = follow spending: where did this coin go?
Backward = follow funding: where did this coin come from?
clean the next tx has exactly one input (forward) or this UTXO's creating tx has exactly one input (backward) — no mixing, provable continuity
mixed multiple inputs were combined — the value is now a blend of sources, chain can't be proven further this way
unspent (forward only) these funds are still sitting at this address, untouched
coinbase (backward only) this is a mining reward — the coin's origin, nothing earlier exists
★ Patoshi — this block matches Sergio Demian Lerner's published "Patoshi pattern" dataset (bensig/patoshi-addresses on GitHub), the ~22,000 early blocks widely attributed to a single miner, commonly believed to be Satoshi Nakamoto. No star ≠ not Satoshi — ~78% of blocks in this era belong to other contemporary miners and simply aren't part of that specific dataset.
