- The coinbase transaction that created the sat
- And for every spend of that sat:
  - The spend transaction
  - The transactions that created the inputs before the input that was spent,
    to determine the values of the preceding inputs, to determine the position
    of the sat
  - And, if the sat was used as fees, all prior transaction in the block in
    which it was spent, and the coinbase transaction, to determine the location
    of the sat in the outputs.

== Reference implementation ==

This document and an implementation of an index that tracks the position of
sats in the main chain are maintained [https://github.com/ordinals/ord here].

== References ==

A variation of this scheme was independently invented a decade ago by jl2012
[https://bitcointalk.org/index.php?topic=117224.0 on the Bitcoin Forum].

For other colored coin proposals see [https://en.bitcoin.it/wiki/Colored_Coins the
Bitcoin Wiki entry].

For aliases, an implementation of short on-chain identifiers, see
[https://github.com/bitcoin/bips/blob/master/bip-0015.mediawiki BIP 15].