Bitcoin Core developers have confirmed that the next software release will eliminate the long-standing 80-byte cap on OP_RETURN outputs, a move expected to expand on-chain data capabilities—but not without controversy.
Lifting the Limit: A New Era for OP_RETURN
In a May 5 GitHub post, Bitcoin developer Gregory Sanders announced that Bitcoin Core’s upcoming version will, by default, relay and mine transactions with OP_RETURN outputs exceeding 80 bytes, and allow multiple such outputs per transaction.
Initially introduced as a gentle deterrent to prevent the overuse of block space for non-payment data, the OP_RETURN limit has long been a constraint on those looking to embed information directly into the blockchain. However, Sanders noted that the restriction has become outdated, and many miners already bypass it.
From Workarounds to Clarity
The change aims to simplify how data is published on-chain. Instead of users crafting complex workarounds—like fake public keys or spendable scripts to hide data—the removal of the cap will streamline data embedding and reduce UTXO bloat. Sanders emphasized that the decision preserves Bitcoin’s security model, citing safeguards like the 4 million weight unit block size cap.
Community Split on the Decision
While the upgrade may boost on-chain utility, it has also sparked debate within the Bitcoin community. Critics like Bitcoin Knots maintainer Luke Dashjr labeled the move as “utter insanity,” while others, including Marty Bent of Ten31 Fund, pointed to a lack of clear consensus.
Opponents fear the change signals a deeper shift in Bitcoin’s direction, potentially straying from its minimalist principles. Still, Sanders maintains that removing the limit aligns with Bitcoin’s ethos of transparent, consistent rules.
As the upgrade approaches, it remains to be seen whether the broader ecosystem will accept the change—or diverge by sticking with earlier versions like Bitcoin Core 29.0 or alternative implementations like Bitcoin Knots.
