
Zcash's NU6.3 Ironwood network upgrade activated at block height 3,428,143 on Tuesday, with the estimated activation time set for roughly 8 a.m. Eastern time. According to the Zebra 6.0.0 release notes, the upgrade introduces a new shielded pool and v6 transaction format, replacing the older Orchard pool system with a separately tracked shielded transaction pool architecture. As of press time, more than 40,000 ZEC have already moved into the new pool, according to migration trackers, with the chain sitting more than 1,500 blocks short of the target when the upgrade was activated. The Zcash Foundation mandates that every node operator upgrade before the fork, with Zebra 6.0.0 already including full support for the new rules. Most ZEC holders do not need to take action today, as their balances remain safe inside the locked pool, with old addresses continuing to work through the new pool's reuse mechanism.
Roughly 176,000 ZEC, worth approximately $81 million, had migrated into Zcash's new Ironwood shielded pool by Wednesday, representing about 5% of the 3.66 million ZEC held in Orchard at activation. According to the latest migration tracker data, Orchard's balance has since fallen to about 3.51 million ZEC, with around 46,000 ZEC crossing over in the past 24 hours. The migration is voluntary, leaving most of Zcash's shielded supply temporarily stranded in a now-closed Orchard pool while holders, wallets and exchanges move funds at their own pace. Orchard can no longer take deposits, with every coin still inside having to leave through the turnstile mechanism that caps total withdrawals at the amount verifiably deposited, so the pool's balance can now only fall.
Zcash gained 3.2% over the past 24 hours and is trading at $475.95 at the time of writing, outperforming a largely flat Bitcoin after the successful rollout of the Ironwood network upgrade. According to crypto.news price data, ZEC briefly fell about 9% to around $460 after the upgrade before recovering to roughly $475, with the token having already experienced significant volatility after the Orchard vulnerability became public, losing more than half of its value before later rebounding from about $45 in September last year to nearly $700 by year-end. Markets have repositioned since June, with developers noting that wallets are still building the tool that moves your funds, so until yours is ready, that balance may appear stuck. Binance held share with approximately 55% of user funds and 24% spot trading, and drew net inflows in early July while the tracked market saw outflows.
Despite the recent 3.2% gain, Zcash remains within its broader bearish structure with technical indicators showing mixed signals. On the daily chart, ZEC is trading above a long-standing support zone between $361.59 and $377, an area that has repeatedly attracted buyers since early May, helping prevent a deeper decline. However, the token has yet to establish a convincing higher high, leaving the broader bearish structure intact. On-Balance Volume (OBV) has remained largely flat before gradually turning lower, suggesting buying demand has been too weak to outweigh selling pressure, while the MACD recently crossed below the zero line, indicating that bearish momentum continues to dominate. The Relative Strength Index (RSI) remains below the neutral 50 level, indicating that the recent price bounce has yet to be supported by stronger market momentum. The four-hour chart reinforces this cautious outlook, with OBV continuing to trend lower, showing that sellers still hold the advantage despite the recent recovery.
The Ironwood upgrade addresses a critical soundness flaw discovered by Taylor Hornby from Shielded Labs on May 29, 2026, which could have allowed attackers to create counterfeit ZEC without obvious public record. The flaw had been undetected for four years since Orchard launched in May 2022, with evidence pointing away from exploitation according to a CoinDesk Research report in July. Orchard's balance grew steadily through the four years the flaw was open, including through last year's price rally, when cashing out would have been most profitable. The turnstile mechanism now caps total withdrawals at the amount verifiably deposited, providing a public check on circulating supply without exposing private balances. As reported by the Zcash Foundation, this mechanism provides users with a public check on circulating supply without exposing private balances or transaction details, leaving any excess hidden value trapped inside Orchard once the pool becomes exit-only. The migration is expected to give node operators a clear, independent way to confirm the circulating supply has not been inflated over time.
The upgrade introduces quantum-recoverable notes through ZIP 2005 specification, allowing shielded notes to be recovered through future post-quantum protocols. According to the official documentation, this feature binds more note data into note construction, enabling later recovery systems to verify ownership without relying solely on cryptography that powerful quantum computers could break. Ironwood also launched with formal verification of its proof circuit, which produces a mathematical proof that software behaves correctly in every possible case rather than only in the cases a tester thought to try. Project Tachyon announced that researchers completed a machine-checked mathematical proof covering Ironwood's balance integrity, providing additional assurance that the new shielded pool cannot create value beyond what has publicly entered it under its stated cryptographic assumptions. The proof was written in the Lean programming language and consists of more than 2,700 theorems developed over more than a month by three teams of researchers and cryptographers.