Bitcoin Core v30.0 released with OP_RETURN limit raised from 80 bytes to 100 KB

Bitcoin (open-source protocol; Bitcoin Core maintainers)/Bitcoin Network & Bitcoin Core

Bitcoin Core v30.0 released October 12, 2025, raising the OP_RETURN data limit from 80 bytes to 100,000 bytes (100 KB). The change split the community: supporters saw it as enabling cleaner data embedding; critics feared legal liability for node operators and increased network spam. Bitcoin Core's market share fell from 88% to 78% after the release as some users switched to alternatives like Knots.