Chainlink Proof of Reserve feeds show exactly where their backing data comes from

How Chainlink Proof of Reserve Feeds Work

@chainlink Proof of Reserve (PoR) feeds give smart contracts a direct way to check whether a token's backing actually exists before executing. Chainlink Proof of Reserve operates through specialized data feeds powered by the same infrastructure as Chainlink Price Feeds. That means developers can read these feeds the same way they read other data feeds, simply by specifying a Proof of Reserve feed address instead of a price feed address.

Each feed is labeled by its data source so integrators know exactly what they are trusting. Offchain reserves use three main methods: a third-party auditor or accounting firm that combines fiat and investment assets into a reported figure; a custodian, where data is pulled directly from the bank or vault holding the assets; or an issuer-run API. For on-chain assets, cross-chain feeds read the wallet addresses a project registers. Some feeds use a wallet address manager contract where the project has self-attested to the addresses it owns, and Chainlink labels these issuer-attested routes so integrators can weigh the trust level accordingly.

As of mid-2026, Chainlink operates over 40 active PoR data feeds across 56 integrated projects, verifying more than $17 billion in reserve assets. The feeds update automatically: Chainlink's oracle network checks reserves off-chain regularly and performs on-chain updates when balances change over a certain threshold, keeping costs manageable without sacrificing timeliness.

Secure Mint Closes the Infinite-Mint Attack Vector

Knowing that reserves exist is useful. Enforcing that knowledge at the moment of minting is where Secure Mint comes in. Chainlink Proof of Reserve's Secure Mint capability enables asset issuers to programmatically require reserves to be greater than or equal to the supply being minted. If backing is insufficient, issuance is automatically halted at the smart contract level.

The stakes are real. One critical threat in digital asset systems is the infinite mint attack, where an issuer mints more tokens than it has backing for, often leading to depegging, insolvency, or complete protocol failure. Past incidents illustrate the risk: Cashio's dollar-pegged stablecoin lost its peg after an infinite mint glitch enabled attackers to mint tokens without posting sufficient collateral, and Cover Protocol was exploited where over 40 quintillion coins were minted, inflating the token supply.

Secure Mint addresses this directly. Attempting to mint tokens beyond available reserves results in the transaction being reverted and no tokens being minted. The same mechanism extends to wrapped assets: once Chainlink Proof of Reserve determines that wrapped tokens are undercollateralized, Chainlink Automation can be used to halt the minting, redeeming, and burning of wrapped tokens.

For stablecoin issuers, wrapped asset protocols, and tokenized real-world asset projects, the combination of labeled reserve feeds and enforced mint controls gives both builders and users a clearer picture of what is actually backing the tokens they hold.

Sources:
Chainlink Documentation: Proof of Reserve Feeds
Chainlink Blog: Secure Mint Explained
Chainlink Education Hub: What Are Proof of Reserves?