Zcash NU7 Upgrade Makes Sprout Funds Unspendable Under Current Rules

The Zcash (ZEC) network’s NU7 upgrade activated at 10:34 p.m. ET Thursday (02:34 UTC Friday), making any ZEC still in Sprout unspendable under current rules. The pool held about 12,226 ZEC on Nov. 5, worth about $16 million at prices that day.

NU7 took effect at block height 3,543,405. It ends support for v4 transactions, the only transaction format that can move funds out of Sprout. Coins left in the pool cannot be transferred under the network’s current rules, even if holders still have valid private keys.

Sprout is Zcash’s earliest privacy pool. The coins left there remain part of the network’s issued supply. Any future ability to move them would depend on a later network upgrade restoring the spending function.

NU7 also shortens the target block time from 75 seconds to 25 seconds, a change intended to reduce the wait for a transaction’s first confirmation. This block-time change is separate from the spending cutoff affecting Sprout balances.