In a policy updated on Nov. 23, ConsenSys said it stores identity information including first names, last names, postal addresses and emails.
The firm also said it keeps IP addresses and wallet information when users send transactions using remote procedure call (RPC) provider Infura on MetaMask.
The news came as a shock to most market participants who rely extensively on Infura to run nodes and MetaMask as their digital wallet.
“Many of us saw this coming a mile away, but now it’s officially confirmed that MetaMask and Infura log your information. They are turning ‘web3’ into the same surveillance panopticon as Web 2.0 and the ethereum people aren’t even paying attention,” tweeted Magic Internet Money podcast host Brad Mills.
Advocates of privacy and decentralization called for users to run their own nodes, or switch over from Infura, which currently accounts for a considerable amount of Ethereum nodes.
In September, Bloomberg reported that over 50% of ETH transactions ran through Infura at times, according to Infura co-founder Eleazar Galano.
MetaMask founder Dan Finlay responded to some of the criticism on Twitter, saying, “I think we can get this fixed soon. We are not using IP addresses even if they are being temporarily stored, which they don’t need to be, as we’re not using them for anything.”
Finlay opted to refrain from more actively convincing users that a change was coming on the grounds that it wouldn’t be appropriate for him to “try to amplify a message undermining legal policy.”