TYPE 0x0701 · COMPOUND FAMILY

TIMELOCKED_SIG

Signature verification combined with a relative timelock (CSV) in a single block. Collapses the common SIG + CSV two-block pattern, saving 8 bytes on wire.

Compound Non-Invertible

Ladder Diagram

Fields

Field	Data Type	Size	Side	Description
scheme	SCHEME	1 B	Conditions	Signature scheme identifier (0x01 = Schnorr, 0x02 = ECDSA). Routes to post-quantum verifier when PQ scheme set.
timelock	NUMERIC	1-4 B	Conditions	Relative timelock in blocks (BIP 68 sequence value)
pubkey	PUBKEY	32-33 B	Witness	Public key (x-only 32B or compressed 33B)
signature	SIGNATURE	64-65 B	Witness	Schnorr signature (64B) or with sighash byte (65B)

Public key folded into Merkle leaf via merkle_pub_key (PubkeyCountForBlock = 1). No key field in conditions.

Wire Format Breakdown

Conditions side (committed in the rung leaf):

0x0701 0 2 SCHEME · 1B NUMERIC · 3B ≈ 11 bytes

Witness side (in input witness):

0x0701 0 2 PUBKEY · 32B SIGNATURE · 64B = 104 bytes

Total (conditions + witness) 150 bytes

Compared to separate SIG + CSV blocks: 157 bytes → 149 bytes (saves 8B / 5.1%)

Evaluation Logic

1. Locate the witness PUBKEY, SIGNATURE, and conditions NUMERIC (timelock); any missing → ERROR. PUBKEY identity is bound at MLSC-proof level via merkle_pub_key — no leaf check here.

2. Read the optional SCHEME conditions field; if absent, default to Schnorr.

3. Dispatch VerifySigWithScheme(PUBKEY, SIGNATURE, scheme, ...). Sig size checks fire here (Schnorr 64-65 B, ECDSA 8-72 B, PQ scheme-specific). Invalid → the underlying result (UNSATISFIED for verification failure, ERROR for malformed inputs).

4. Then run the CSV check (mirroring CSV block): ReadNumeric the timelock; undecodable → ERROR

5. If SEQUENCE_LOCKTIME_DISABLE_FLAG (bit 31) is set in timelock → SATISFIED immediately (no further check).

6. Range guard: timelock < 0 or > 0xFFFFFFFF → UNSATISFIED (protects the narrowing cast).

7. CheckSequence(uint32_t(timelock)); fails → UNSATISFIED; passes → SATISFIED

Return Values

Condition	Result
PUBKEY, SIGNATURE, or NUMERIC missing	ERROR
Signature size out of range for the resolved scheme	ERROR
Timelock NUMERIC undecodable	ERROR
Signature verification fails	UNSATISFIED
SEQUENCE_LOCKTIME_DISABLE_FLAG set after a valid signature	SATISFIED
Timelock out of uint32 range, or `CheckSequence` fails	UNSATISFIED
Signature valid AND timelock satisfied	SATISFIED

JSON Wire Format

Conditions (committed in the rung leaf)

{
  "type": "TIMELOCKED_SIG",
  "inverted": false,
  "fields": [
    { "type": "SCHEME", "hex": "01" },
    { "type": "NUMERIC", "value": 144 }
  ]
}

Witness (input)

{
  "type": "TIMELOCKED_SIG",
  "inverted": false,
  "fields": [
    { "type": "PUBKEY", "hex": "02abc1...33 bytes" },
    { "type": "SIGNATURE", "hex": "30440...64 bytes" }
  ]
}

The timelock NUMERIC lives in conditions only — it is not duplicated in the witness. After MergeConditionsAndWitness the evaluator sees SCHEME, NUMERIC, PUBKEY, SIGNATURE in a single merged block.

Use Cases

Lightning Channel Force Close

The to_local output in a commitment transaction requires the broadcaster's signature after a CSV delay. TIMELOCKED_SIG encodes this in one block instead of two, reducing witness overhead across all commitment transactions.

Vault Recovery Path

Hot wallet spending with mandatory cooling-off period. The hot key can sign, but the transaction is only valid after N blocks have passed since the UTXO was confirmed.

Inheritance Planning

Beneficiary can claim funds after an extended CSV delay (e.g., 26,280 blocks / ~6 months), proving liveness-failure of the original owner.

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