OP_CHECKTEMPLATEVERIFY (CTV)

OP_CHECKTEMPLATEVERIFY (CTV), specified in BIP 119 by Jeremy Rubin, is a proposed Bitcoin opcode that commits an output to a specific spending-transaction template. When a coin locked with CTV is spent, the opcode hashes a defined set of fields of the spending transaction (the outputs, the number of inputs, amounts, and similar data) and checks that hash against a 32-byte value baked into the script. If they do not match, the spend fails. CTV is a proposed soft fork; it is not active on mainnet and remains under community review.

Deliberately limited

CTV provides the narrowest useful form of transaction introspection. Because the template is a fixed, fully enumerated hash rather than a programmable expression, CTV produces non-recursive covenants with no dynamic state: a coin can be forced to flow into a predetermined next transaction, but that next transaction cannot itself re-impose arbitrary new rules. This restraint is intentional and is part of why CTV is often described as one of the more conservative covenant designs.

What it enables

By pre-committing to where coins must go, CTV supports self-custody vaults, congestion-control transaction trees that batch many payouts behind one on-chain output, payment pools, and more efficient channel constructions. It does this without exposing keys to new signing modes, since the commitment is purely a hash comparison.

CTV is frequently discussed alongside the general idea of a covenant and the congestion control tree it makes practical. D-Central presents this as an explanation of an open proposal, not an endorsement of any activation path.