Starknet launches STRK20 for shielded ERC20 balances

Starknet has launched STRK20, a zero-knowledge privacy framework that lets ERC20-like tokens on its network offer shielded balances and private transfers. The framework’s first major deployment is strkBTC, a bitcoin‑denominated token that can move between public and private modes inside the Starknet ecosystem.

STRK20 is a developer-facing standard that embeds shielding into token contracts. Projects can add private transaction flows directly into token logic rather than building a separate privacy stack. The framework supports common token activity such as transfers, swaps, lending, staking, payments and donations while keeping shielding part of how an asset behaves.

The design includes disclosure mechanisms intended to meet regulatory and compliance needs. Viewing keys are built to allow disclosure of information only when presented with legally binding requests, rather than revealing full transaction histories to third parties. The framework aims to keep privacy at the protocol level while retaining controlled on‑chain access for authorities when required.

Starknet’s team contrasted STRK20 with mixer services. Mixers typically move funds to other addresses to obscure history; STRK20 integrates shielding into token operations so assets do not have to be relocated to a separate destination for private use.

Technically, STRK20 uses zero-knowledge proofs to confirm private state changes and transfers without revealing underlying details. That lets contracts validate transactions and balances while keeping amounts and counterparties hidden from the public ledger. Developers can adopt the standard for new or existing ERC20-style tokens to offer optional private balances alongside public ones.

strkBTC is the first token to implement STRK20. The token allows bitcoin-denominated balances to exist in both visible and shielded forms and to switch modes through compatible wallets and applications on Starknet.

Damian Chen, vice president of growth at the Starknet Foundation, described the framework as enabling “users, builders, and institutions to maintain confidentiality from the public while preserving compliance-ready disclosure paths when required by law.” Eli Ben-Sasson, CEO of StarkWare, predicted that zero-knowledge privacy tools could allow future regulatory investigations to target specific information with less impact on unrelated wallets.

Starknet presents STRK20 as a standard to help token issuers and application developers add private transaction options while retaining mechanisms for lawful disclosure and on‑chain compliance controls.