According to Foresight News, Udi Wertheimer, the co-founder of Taproot Wizards and advocate of OP_CAT, has announced that the OP_CAT proposal has officially received its BIP number, BIP-420. The proposal supports Bitcoin contracts, allowing for smart contracts, secure bridges, on-chain transactions, and zk proof verification. The OP_CAT opcode is expected to simplify and expand Bitcoin's functionality, including making decentralized protocols more practical and supporting advanced multi-signature setups.
OP_CAT was initially included as one of the earliest opcodes in Bitcoin. However, due to concerns about creating scripts that could potentially lead to vulnerabilities, the anonymous creator, Satoshi Nakamoto, disabled it along with several other opcodes in 2010. The BIP-420 proposal, written by Ethan Heilman and Armin Sabouri, aims to reintroduce OP_CAT to Bitcoin through a backward-compatible soft fork by 'redefining opcode OP_SUCCESS126'. This uses the same opcode value as the original OP_CAT, aiming to eliminate any potential confusion by not using different opcode values. The proposal focuses solely on reintroducing the opcode, without changing other aspects of script operation limits.
The possibility of an OP_CAT soft fork depends on a combination of technical, security, and community consensus considerations. Without widespread consensus and clear evidence of its safety and utility, the implementation of OP_CAT remains uncertain.