The KuCoin custodial exchange migrated Legacy NEO and GAS held on its platform to N3 NEO and GAS on June 20, 2023. NEO token holders did not need to take any action to participate in the migration process, as the Legacy to N3 assets were automatically swapped at a 1:1 ratio. Users can now deposit and withdraw NEP-17 NEO and GAS.

Moving forward, KuCoin will not support Legacy NEO or GAS, and the exchange implores users not to deposit any NEP-5 assets. Further, NEO or GAS withdrawn from the platform must be sent to an N3 wallet with an address that starts with the letter “N.”

KuCoin launched out of Hong Kong in Sep. 2017 and offered support for Legacy NEO and GAS the following month, becoming the first custodial exchange to use NEO as a quote currency. Additionally, KuCoin was the first exchange that listed many of the NEP-5 tokens that launched on Neo in 2017 and 2018. KuCoin is ranked 22nd in 24-hour trading volume on CoinMarketCap.com, with approximately US $627.3 million.

The full announcement can be found at the link below:
https://www.kucoin.com/news/updates-on-the-migration-of-neo-and-gas-tokens-from-neo-legacy-to-neo-n3-network-20230620