Ethereum zero-knowledge (ZK) layer-2 scaler zkSync has faced backlash from crypto industry watchers for a claimed lack of anti-Sybil measures and unfair distribution for the airdrop of its self-titled token, zkSync (ZK).

“zkSync airdrop is out. Most farmable and farmed airdrop ever probably,” Mudit Gupta, the information security chief of rival layer-2 network Polygon wrote in a June 11 X post.

“Almost no Sybil filtering as far as I can see,” Gupta added. “Anyone who knew the criteria could’ve easily farmed the shit out of it.”

Earlier that day, zkSync said that 695,232 wallets could claim its ZK token airdrop and shared a list of seven eligibility criteria, which it said aims to protect against Sybil attacks — where an entity uses multiple wallets to game crypto airdrops.

“That was not a well-planned airdrop from a Sybil perspective,” Cinneamhain Ventures partner Adam Cochran said, sharing zkSync’s eligibility criteria. “Those criteria are easy to not hit as a real user, and easy to hit as a farmer, and had no anti-Sybil program.”

The backlash saw crypto analytics firm Nansen step in to clarify it didn’t perform anti-Sybil checks or advise on allocations for the ZK token drop, but “provided data on some specific wallet segments” including for “whales and known scammers.”

However, crypto researcher “Ignas” highlighted that zkSync purposefully didn’t apply strict anti-Sybil measures, noting its press release claimed, “Sybil detection often cuts out real users with arbitrary filters.”

Sybil-tracking X account “Sybil Horror 6” posted a preliminary estimation using data from LayerZero Labs, claiming 135 million ZK tokens could be headed for Sybil wallets as listed by LayerZero.

Related: ZkSync’s Gemholic project suspected $3.5M rug pull

Based on ZK’s price on pre-market perpetual exchanges Aevo and PancakeSwap, the tokens could be worth up to $52.3 million.

The token has dropped around 43% in the past 24 hours on both markets, with sharp drops coinciding with zkSync releasing details of its airdrop.

Matter Labs, zkSync’s development firm, did not immediately respond to a request for comment.

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