OP_RETURN bytes 80 about colored-coins-protocol-specification HOT 1 CLOSED

@onepix, first of all thank you for the notice - the wiki is now updated to indicate 80 bytes, this is the current max size used by the Colored-Coins protocol implementation.
80 bytes OP_RETURN is supported since bitcoin-core's 0.11.0.

Colored-Coins transactions exploit up to 80 bytes, it depends on the data needed to be encoded.
Specifically, it depends on the varied amount of bytes needed to encode: transfer instructions, metadata torrent-hash and meta-data SHA2 (for transactions carrying meta-data), and the amount of asset units to issue (for issuance transactions).
Colored-Coins protocol implementation by Colu will always use more than 40 bytes OP_RETURN for transactions which carry meta-data, because it pushes 20 bytes of torrent-hash plus 32 bytes of the meta-data SHA2.
The rest of Colored-Coins transactions may use more than 40 bytes, but not necessarily.
The full coloring scheme can be found here .

from colored-coins-protocol-specification.