Zcash migration reaches 85% completion as Orchard pool winds down to 3% of supply

Zcash’s emergency migration from its compromised Orchard shielded pool to the new Ironwood pool has hit the 85% mark, with just 3% of the total supply still sitting in Orchard. The Ironwood pool has already accumulated over 3.7 million ZEC, with migration speeds reportedly reaching thousands of ZEC per hour. From bug discovery to full migration On May 29, 2026, Zcash developers discovered a soundness vulnerability in the Orchard shielded pool. The flaw could have allowed undetectable counterfeiting of ZEC. The response came in two phases. First, an emergency patch to stop the bleeding. Then, the more comprehensive NU6.3 upgrade, which introduced Ironwood as a replacement pool with formal verification and quantum-resilient cryptographic elements. Ironwood went live on July 28, 2026, at block 3,428,143. At that moment, the Orchard pool was officially sealed. Users were expected to move their funds voluntarily through a turnstile mechanism defined by ZIP-318, which preserves privacy during the transfer process. At the time Ironwood activated, shielded supply in Orchard represented roughly 25% of all circulating ZEC. Why 85% matters more than it sounds Mid-August snapshots had the migr...