# Researchers Propose Shielded Bitcoin Privacy Layer Without a Consensus Change

By Simon Yoon

Canonical URL: https://www.tokenpost.com/news/technology/23807
Published: 2026-09-24T15:46:21.000Z
Updated: 2026-09-24T15:46:21.000Z

Researchers Clara Shikhelman, Misha Komarov and Aleksei Moskvin have proposed Shielded Bitcoin, a privacy layer intended to support shielded transactions on Bitcoin without changing the network’s consensus rules.

The design would operate without a soft fork, an operator or changes to Bitcoin consensus. Instead, it would define its own transaction format and indexing process while using Bitcoin PIPEs to anchor deposits and withdrawals.

Shielded Bitcoin transactions would carry prefixed data, including the marker shbtc:. That data could be placed in OP_RETURN, witness fields or other transaction data fields. The Bitcoin network would not validate or enforce Shielded Bitcoin’s rules, meaning transactions that fail those rules could still be recorded on the blockchain.

Independent Shielded Bitcoin indexers would interpret the transaction history. Indexers would ignore invalid transactions and reject corresponding balance-state updates when verification fails. This creates a separate accounting layer that operates on top of Bitcoin’s records rather than changing how Bitcoin nodes process consensus transactions.

The protocol would represent shielded funds as notes corresponding to Bitcoin UTXOs. Indexers would reconstruct which notes remain available and which have been spent by examining the transaction history. They would maintain a set of nullifiers, identifiers used to mark spent notes without deleting them from the system.

Zero-knowledge proofs would demonstrate that each nullifier was created from a valid note. This would allow the protocol to verify that funds were authorized and had not already been spent while limiting the transaction details revealed publicly. The design aims for privacy comparable to Zcash’s shielded pool.

Recovering funds would require a Bitcoin node and a Shielded Bitcoin indexer. The proposal does not require a service provider, coordinator or off-chain state, so users would rely on the blockchain and indexing rules to rebuild their balances.

The proposal’s structure mirrors Bitcoin’s UTXO model, but its validation and balance tracking would occur through the Shielded Bitcoin indexing layer rather than through Bitcoin’s consensus process.