Part V · 2016 to 2026
Ten years
From the genesis block to NU5, which ended the need for any ceremony, through two halvings and an emergency, to the tenth anniversary. Upgrades and votes follow the ZIPs and this site's own records.
Since the genesis block3,620 days
To the tenth anniversary32 days
In Ironwood now3.99M ZEC383.66K ZEC still in Orchard · block 3,496,325
2016
Launch
- Oct 28 · GenesisMainnet launches with Sprout shielded transactions, a 21M cap, 2.5-minute blocks and a 12.5 ZEC subsidy, ramped in over a 34-day slow start. The Founders’ Reward directs 20% of the subsidy to the founding team, investors and the Zcash Foundation for the first four years, 10% of total supply.
2018
The quiet save, then Sapling
- Mar 1 · A flaw foundAriel Gabizon finds a flaw in the proving system Sprout used that could have allowed invisible counterfeiting. It is fixed quietly by the Sapling upgrade in October and disclosed in February 2019. No evidence of exploitation was ever found.
- Oct 28 · SaplingA redesign of shielded transactions cuts proving time and memory sharply, making shielded payments practical on phones. It ships on the network’s second birthday, on parameters from a new, larger ceremony.
2019
Blossom
- Dec 11 · 75-second blocksBlock time drops from 150 to 75 seconds and the per-block subsidy from 12.5 to 6.25 ZEC, keeping issuance per hour unchanged. It is why the first halving lands on 3.125, not 6.25.
2020
First halving and the Dev Fund
- Jul · HeartwoodShielded coinbase: miners can receive block rewards directly into shielded addresses.
- Nov 18 · Canopy, the first halvingThe subsidy halves to 3.125 ZEC. The Founders’ Reward ends and ZIP 1014’s Dev Fund begins: 7% to Bootstrap (ECC), 5% to the Zcash Foundation and 8% to Major Grants, run by ZOMG and renamed Zcash Community Grants in February 2022.
2022
NU5: no more ceremonies
- May 31 · Orchard and Halo 2The Halo 2 proving system removes the trusted setup for the new Orchard pool, and Unified Addresses bundle transparent, Sapling and Orchard receivers into one address.
- Jun · SandblastingA sustained spam attack bloats the chain and exposes wallet sync pain. It forces the fee overhaul of ZIP 317 and a generation of faster sync work.
2024
Second halving and the lockbox
- 2023–2024 · New stewardsZooko steps back from ECC leadership, Zashi ships as ECC’s mobile wallet, and Zebra, the Foundation’s Rust node, reaches production alongside zcashd.
- Nov 23 · NU6, the second halvingThe subsidy halves to 1.5625 ZEC. 8% goes to Zcash Community Grants, paid to the Financial Privacy Foundation, and 12%, 0.1875 ZEC per block, accrues in an in-protocol lockbox.
2025
Coinholders take the wheel
- Nov 24 · NU6.1The lockbox pays its 78,750 ZEC to a coinholder-controlled fund, and the 8% and 12% streams continue to the third halving (ZIP 271, ZIP 1016). Coinholders now vote on grants from the fund; key-holders sign the payouts.
2026
The Orchard emergency, then year ten
- Mar 16 · A vetoTwo key-holders, the Zcash Foundation and Shielded Labs, announce a veto of the $2.67M Q4 2025 grant to Bootstrap (ECC), approved by coinholders months earlier.
- Jun 2–3 · The Orchard emergencyA soundness flaw in the Orchard circuit leads to an emergency soft fork that disables Orchard at block 3,363,426; the NU6.2 network upgrade at block 3,364,600 re-enables it with a corrected circuit (ZIP 257).
- Jul 28 · IronwoodNU6.3 activates at block 3,428,143 with a new shielded pool, Ironwood (ZIP 258). Orchard stops taking new funds, and balances move out into Ironwood.
- Sep 14 · NU7’s scopeCoinholders vote to keep the halvings, retire v4 transactions at NU7 and move to 25-second blocks; 2.4M ZEC took part in the first question. They also back reissuance from February 2031, but coinholder and community polls reach no shared majority on the date, and NU7 takes 2031 as the more conservative choice.
- Oct 28 · Ten yearsTen years since the genesis block.
Every activation height and how it was decided is on Zcash governance; every ZEC paid outside mining on Zcash's Since block zero.
Often misstated
“The reward halved from 12.5 to 6.25 in 2020”No. Blossom (2019) moved to 75-second blocks and 6.25 ZEC per block with unchanged hourly issuance. The 2020 halving went to 3.125, and 2024 to 1.5625.
“Zerocash created zk-SNARKs”Zero-knowledge proofs date to 1985, and the first known SNARK construction, Micali’s CS proofs, to 1994; the zk-SNARKs Zerocash used come from the early 2010s. Zerocash was the first full payment design built on them, hiding sender, receiver and amount; Zcash made it run in production.
“Zcash is governed by a DAO”There is no Zcash DAO. Decisions run through the ZIP process, ZCAP and coinholder polls, coinholder votes on the fund (ZIP 1016) and independent organizations. ZecHub runs a DAO, and it governs a community project, not the protocol.
“ZOMG runs the Major Grants”Not since February 2022, when Zcash Open Major Grants was renamed Zcash Community Grants. It still funds independent teams doing major ongoing development; since NU6 in November 2024 its stream is paid to the Financial Privacy Foundation.