Wrapped Token

Why are wrapped tokens needed, and what problems do WETH and WBTC solve?

WETH — the background problem: When Ethereum was designed, native ETH predated the ERC-20 token standard — ETH is not an ERC-20 token and cannot be used directly in DeFi contracts that require the ERC-20 interface. Solution: deposit ETH into a contract; the contract issues you an equivalent amount of WETH (Wrapped ETH), which is a standard ERC-20 usable in all DeFi protocols. On redemption, return WETH to the contract and receive ETH back. Most modern DeFi protocols handle ETH directly, but WETH remains widely used.

WBTC — the background problem: Bitcoin and Ethereum are entirely different blockchains; BTC cannot be used natively on Ethereum. WBTC lets users deposit BTC with trusted custodians (currently primarily BitGo and BiT Global), receiving an equivalent amount of WBTC (ERC-20) on Ethereum, enabling Bitcoin holders to participate in Ethereum DeFi.

Both follow the same logic: "locked in location A, receive representation in location B" — which is also the fundamental operating principle of cross-chain bridges.

What are the risks of using wrapped tokens, and what is custodian risk?

Wrapped token risks fall into three categories:

(1) Custodian Risk: WBTC and similar tokens require a trusted third party to hold the original assets. If the custodian goes bankrupt, is hacked, or misuses assets (e.g., over-issuance), holders may be unable to redeem 1:1 for BTC. This is a "centralized" trust assumption, somewhat at odds with the ethos of decentralized DeFi.

(2) Bridge Contract Risk: WETH and similar tokens depend on contract security. If the contract has a vulnerability and is exploited, all native assets locked inside may be lost.

(3) Depeg Risk: Under extreme market stress, wrapped tokens may briefly trade at a discount, unable to fully reflect their 1:1 peg value. Usually caused by market liquidity crises or shaken confidence in the custodian.

Evaluation metric: check the custodian's Proof of Reserve — WBTC publishes daily BTC holdings vs. WBTC issued, verifiable directly on-chain.

Are there alternatives to wrapped tokens that don't rely on custodians?

(1) Decentralized BTC wrapping (e.g., tBTC v2): tBTC uses a decentralized validator network and crypto over-collateralization to custody BTC, without relying on a single institution. Anyone can mint and redeem without KYC. The tradeoff: far lower liquidity than WBTC (as of 2025, tBTC supply is roughly 1/100th of WBTC or less).

(2) Native cross-chain standards (e.g., IBC): The Cosmos ecosystem's IBC protocol allows tokens to be natively transferred between chains without wrapping — the asset itself moves between chains rather than being locked and re-issued. However, this only works between chains using the same cross-chain communication standard.

(3) Aggregated liquidity solutions: some DeFi protocols (e.g., Across Protocol) allow direct swaps between chains without manual wrapping — the wrapping process is invisible at the user level.

In practice: WBTC and WETH continue to dominate DeFi usage through first-mover advantage and deep liquidity.

How are wrapped tokens related to Liquid Staking Tokens (LSTs)?

Liquid Staking Tokens (LSTs, such as stETH, rETH) are an extension of the wrapped token concept but add a "staking yield" dimension.

Ordinary wrapped token (WETH): 1 WETH = 1 ETH, no additional yield, just standardization.

LST (stETH): users stake ETH and receive stETH. The stETH quantity automatically increases daily to reflect staking rewards (Lido model), or stETH quantity stays constant but each stETH can be exchanged for increasingly more ETH over time (rETH model).

Common ground: both follow the "lock in A, receive representation of B" logic, and both carry depeg risk.

Difference: LSTs represent not only the underlying asset but also "future staking yield," making their pricing logic in DeFi compositions more complex. In a depeg event, the loss is not just principal — it includes expected yield.