On October 6, 2026, Winklevoss Asset Services filed a Form S-1 with the SEC for a spot Zcash ETF under the proposed ticker WINK — a direct-holding fund, custodied by Gemini Trust Company, charging a 0.25% annual sponsor fee, with Winklevoss Capital Fund indicating non-binding interest in up to $100 million of shares (The Block; Coinpedia). It is the third such filing, after Grayscale's ZCSH — live on NYSE Arca since August 25 — and an unapproved Bitwise application. Grayscale's fund was approaching $1 billion in net assets by late September, though net inflows had already gone quiet: no new money came in on September 23–25, and the fund recorded its largest single-day outflow, about $8.12 million, on September 28 (Tronweekly; Bitcoin.com News).

Zcash's entire differentiator — optional shielded transactions, where sender, receiver and amount aren't visible on-chain — is also the one thing a listed ETF structurally cannot hold. A custodian has to prove reserves; Gemini- and Coinbase-style custody arrangements work from addresses and balances a regulator or auditor can verify. Shielded ZEC sitting in a z-address (a shielded address — the opposite of a transparent t-address) is unprovable by design. So whatever these funds hold is, definitionally, the transparent slice of the asset, not a cross-section of it.

That matters for On-chain Usage & Economics, the framework's second-heaviest dimension at 22 of 100 points, because it scores real usage from exactly the data shielding removes: active addresses, transaction values, holder distribution. The evidence here is unsettled before a single ETF share changes hands. Trackers don't agree on how much of ZEC's supply is even shielded right now: ZEC Stats put it near 31% (about 5.15 million ZEC) in an update as of late August 2026, up from roughly 8% in early 2025 (DataWallet, citing ZEC Stats); a CoinGecko-based count put it at about 27.5% (4.5 million of 16.34 million circulating) in an October 2025 reading (CoinCentral); The Block measured 23% of total supply in November 2025, up from 18% the month before (The Block). Different dates, different denominators — circulating supply versus total supply — and a multi-point spread in the same stretch of weeks, for a figure meant to describe one chain's current state rather than a forecast.

The asset's entire pitch is that no one can see your coins; the ETF wrapper's entire pitch is that someone can always see the fund's.

Worth separating from this: nothing here touches hard gate 8, custody that can freeze, mint or seize. That gate asks whether a central party controls the protocol's own keys — ZEC's issuance and freeze properties are unchanged by who custodies shares in a fund built around it. An ETF custodian holding provable reserves is a different question from protocol-level control, and a rules-based framework shouldn't conflate the two just because both use the word "custody."

There's also a Market Structure (8 of 100 points) footnote in Grayscale's own numbers: as of September 24, cumulative net inflows stood at $306.12 million against $1 billion in net assets — meaning most of the fund's size came from ZEC's price roughly doubling since listing and from converting an existing 2017-vintage trust, not from new capital (Bitcoin.com News). A related-party transaction did some of that work directly: on September 8, Grayscale's parent DCG exchanged roughly 85,705 ZEC for about $100 million in ZCSH shares. A headline AUM figure and a liquidity figure are not the same measurement, and the framework should keep asking which one a given number actually is.