Thu 6 Aug 2026

Bitcoin's OP_RETURN opcode has been used to embed data in on-chain transactions since 2014, with three distinct usage waves recorded in 2019, 2024, and 2025 — the latter almost entirely driven by the Runes protocol. Despite Bitcoin Core 30 raising the default OP_RETURN size limit from 80 bytes to approximately 4MB in late 2025, the volume of nonstandard OP_RETURN outputs did not increase following the policy change. This contradicts predictions that relaxed standardness rules would trigger a data-embedding surge, indicating that block space economics — not relay policy — remain the binding constraint on on-chain data storage.

Not submitted.