Zcash Sets Ironwood Upgrade for July 28 as ZEC Jumps 7% to $501.62

According to Zcash developer Sean Bowe, the Ironwood mainnet upgrade has been set for July 28 at block 3,428,143, with major Zcash-supporting organizations committed to activating NU6.3 at that height. ZEC rose 7.26% to $501.62 on the announcement.

The upgrade addresses a soundness flaw discovered in the Orchard shielded pool in late May that could have allowed counterfeit ZEC creation. Developers deployed emergency patches in early June, temporarily disabling Orchard before preparing the longer-term Ironwood fix. Ironwood introduces a new shielded pool with revised Orchard code and a public accounting checkpoint—termed a turnstile—requiring funds to pass through a visible verification point before entering the new pool.