Zcash’s privacy claims faced a direct challenge after Arkham Intelligence linked 53% of ZEC belonging to identified companies.
Summary
- Arkham Intelligence documented over 53% of all Zcash transactions and linked $420 billion in ZEC volume to individuals and institutions.
- Tracking includes 48% of all inputs and outputs and 37% of ZEC’s total balance, about 2.5 billion, according to research published by Arkham.
- Zcash founder Zooko Wilcox clarified that fully secure transactions are always cryptographically protected and that Arkham cannot access the protected pool.
Blockchain analytics company Arkham Intelligence published a study revealing that it recorded more than 53% of all Zcash transactions, placing nearly $420 billion in ZEC volume among virtual individuals and institutions. The study, published in December 2025, immediately sparked a debate about the true level of the Zcash privacy model of entry.
Arkham’s tracking includes 48% of all entries and results and links 37% of ZEC’s total balance, about $2.5 billion, to fictitious entities. The company did not break Zcash’s cryptography. It combined corporate collection, exchange data, known government seizures, and transparent address analysis to pinpoint the activity of real-world actors.
Why Arkham can track most Zcash activity but not all
An important distinction is between transparent and secure transactions. Zcash privacy is in. Users choose between T-addresses, which are fully visible in the public ledger, and Z-addresses, which use zero-information proofs to protect the sender, receiver, and value.
“[Arkham] he did not release the name of the ZEC that was stored in the resting place,” said Zcash founder Zooko Wilcox in response to this announcement.” Tracking such transactions “will not be possible because the information is not there,” he added.
As of December 2025, less than a quarter of all ZEC in use is sitting in a secure environment. A lot of work goes through transparent addresses, especially in medium-sized exchanges that almost exclusively use T addresses. Crypto.news has tracked the financial volatility driving ZEC’s recent 73% monthly gain as the quantum and privacy narrative sparks renewed interest.
Why the Arkham reveal is important as the ZEC and NU7 meetings approach
The dispute resurfaced in May 2026 as ZEC grappled with quantum computing issues and the development of the NU7 network. The Orchard shielded pool offers stronger privacy guarantees than the old Sapling pool, but still retains a handful of ZEC functions.
Until the use of the secure pool becomes more widespread, Arkham-style behavior analysis of transparent activity will remain possible for most network activities.
Crypto.news has put together a timeline of quantum threats, including research that shows Bitcoin elliptic curve cryptography requires about 2,330 logical qubits to break. Privacy protocols with a zero-knowledge proof infrastructure are increasingly being discussed as potential safe harbors as those time periods grow rapidly.
Crypto.news also noted Citi’s analysis that a quantum attack on large financial institutions could endanger $2 to $3.3 trillion of GDP, a context that makes Zcash’s NU7 privacy development directly relevant to institutional risk managers looking at the area.
