SIP-1: The Burn Transaction Format

• Status: Frozen (2026-09-23, approved by Rob). The freeze condition, one burn relayed and mined on the public Zcash testnet through third-party peers, was met by txid 641cc3068557651ed4a0e1d4664a14ad4745bcf7a89ce4d9b251313e6f51d231 (10,000 zat burned), broadcast from our testnet zebrad and mined at height 4,383,754 in block 0021b6fbbae671108ee99f1a1e57d285c9c54deab13085b0575e3a847014cf57 by an unrelated miner (coinbase to tmSQnvRGQptJWESW2RQbygmEw744wpkYzdU). Our node recognized it as a SIP-1 burn (box/sip1-relay-check.sh, MATCH: yes). Changing any rule below now takes a new SIP.
• Implementation: crates/consensus/src/sip1.rs (normative reference)
• Author: Sova (orchestrated draft)

Abstract

A Sova mining act is one Zcash transparent transaction that provably destroys ZEC and names the EVM address to credit. This SIP defines the transaction’s on-chain format and the total, deterministic recognition rule every Sova node applies.

The burn transaction

A transaction is a burn iff its transparent outputs satisfy all of:

1. Exactly one payload output: value-0, script exactly OP_RETURN OP_PUSHBYTES_27 <payload> (29 bytes; no PUSHDATA alternates, no trailing bytes). Payload layout, 27 bytes:

   bytes	field
   0–1	magic "SV" (0x53 0x56)
   2	version = 0x01
   3–22	EVM address credited
   23–26	signal bits, big-endian u32 (BIP9-style upgrade signaling)

2. One or more burn outputs: value paid to the canonical eater script — standard P2PKH whose hash160 is twenty zero bytes (76a914 00…00 88ac). No preimage of the zero hash is known; the value is computationally unspendable.

3. Dust floor: summed eater value ≥ 1,000 zatoshis (anti-spam constant; soft-forkable upward).

The burn’s weight is the summed eater value. A transaction with zero payload outputs, two or more payload outputs (ambiguous), an undecodable payload, or insufficient eater value is not a burn — malformed burns never error; they simply don’t exist. The rule is total: every possible transaction deterministically either is a burn or is not.

Relay properties

The payload script (29 bytes) fits Zebra’s default 83-byte datacarrier standardness cap (zcashd MAX_OP_RETURN_RELAY parity; policy applied on all networks, verified in Zebra source). ZIP-317 conventional fees apply to burn transactions like any other (a 1-in/3-out burn ≈ 3 logical actions ⇒ 15,000 zat minimum fee); the fee pays Zcash miners and never counts toward burn weight. Burns MAY be funded by a z→t deshielding transaction — the shielded pool breaks the funding linkage (see the miner’s “Anonymous funding” documentation for honest caveats).

Rationale

• One-payload strictness makes crediting unambiguous without ordering rules. Linear weight makes splitting pointless (Sybil-proof by arithmetic). The zero-hash eater is recognizable without address machinery and provably outside anyone’s control.