Bitcoin Core 30 Expands OP_RETURN to 100k Bytes
Bitcoin Core 30, released October 13, 2025, delivers major security, performance and scalability enhancements. The standout upgrade in Bitcoin Core 30 expands the OP_RETURN limit from 80 bytes to 100,000 bytes, boosting non-financial data capacity for protocols like Runes. The update also adds optional node encryption to protect peer connections, redesigns the orphan transaction buffer to improve DoS resistance and reintroduces external signing support for Windows. Miners gain a new IPC interface for Stratum v2, while coinstatsindex and RPC APIs receive increased flexibility. The GUI moves to Qt6, adding dark mode on Windows and Metal support on macOS, as legacy BDB wallets reach end-of-life (nodes can migrate via migratewallet). Branches 27.x and earlier are deprecated. While supporters argue the expanded OP_RETURN limit enables new use cases, critics warn it risks blockchain bloat, higher storage costs and slower node sync. Traders should monitor mempool size, transaction fees and node performance as the network adjusts to increased data throughput.
Neutral
By expanding the OP_RETURN limit and adding node encryption, Bitcoin Core 30 improves network capabilities without introducing immediate price catalysts. The update enhances security and enables new on-chain data use cases, but raises blockchain bloat and performance concerns. Historical network upgrades like SegWit and Taproot produced neutral to modest price impacts, suggesting traders may see stable conditions in the short term and potential long-term benefits as use cases develop.