Ordinals, inscriptions and the OP_RETURN debate

Data in blocks: what it is, why people disagree, and what Bitcoin Core 30 changed.

Since 2023, the Ordinals protocol lets people number individual satoshis and attach inscriptions, such as images, in Taproot witness data.

The concern

Some see this as spam that raises fees and fills nodes' disks. Others see it as paying users of block space.

What the rules say

Inscriptions follow consensus rules and pay fees. Node policy decides only what a node relays, not what is valid in a block.

Bitcoin Core 30 (10 Oct 2025)

-datacarriersize default raised to 100,000, which "effectively uncaps" OP_RETURN data in relay policy.
Multiple OP_RETURN outputs per transaction are now relayed.
Node operators can set -datacarriersize=83 to restore the old limit.

Bitcoin's answer

The block weight limit caps how much data can ever be added, so a full node stays affordable. Fees price block space: anyone storing data must outbid payments. And each node operator chooses its own policy.