Zcash NU7 Upgrade Activated, Approximately 12,200 ZEC Temporarily Unspendable

On November 6, according to Cointelegraph, the Zcash NU7 network upgrade has been activated at block height 3,543,405, with approximately 12,224 ZEC (worth about $15 million) from the legacy Sprout privacy pool unable to be spent under current rules. The upgrade rejects version 4 transactions, which were the only transaction format supporting spending Sprout funds.

The report notes that these tokens have not been burned, and future network upgrades may restore access, but they may also never re-enable spending functionality. NU7 reduces the target block interval from 75 seconds to 25 seconds and introduces a network sustainability mechanism that removes 60% of transaction fees from circulation to be reissued in the future through mining rewards.

[TechFlow]