According to the source, publicly traded firms are accumulating Ethereum (ETH) with aggregate holdings measured in billions across listed funds and select corporate treasuries, making ETF flow and filings data key for trade timing. Source: issuer daily holdings disclosures; SEC fund filings; HKEX company announcements. Historically the largest disclosed holders among public market vehicles include Grayscale Ethereum Trust (ETHE), which reported multi‑million ETH holdings in public reports around 2023–2024, alongside spot Ethereum ETFs that publish daily unit holdings and custodial balances. Source: Grayscale public reports; U.S. ETF issuer websites; SEC filings. Corporate treasury exposure remains concentrated, with Meitu disclosing roughly 31,000 ETH purchases in 2021 via HKEX announcements, while most U.S.-listed corporates have not reported material ETH on balance sheets. Source: Meitu HKEX announcements dated March 7, 2021 and April 8, 2021; U.S. company 10‑Q/10‑K filings. For trading, monitor spot ETH ETF net creations/redemptions, issuer-reported holdings snapshots, and custodian wallet inflows (commonly at Coinbase Custody for U.S. products) to gauge incremental buy pressure and potential liquidity tightening. Source: ETF issuer daily files and prospectuses; SEC filings; custodian disclosures. Track institutional positioning via quarterly 13F filings for ETH ETFs and crypto-adjacent equities, and cross-check derivatives signals such as CME ETH futures basis and borrow/funding rates to align entries with flow-driven moves. Source: SEC Form 13F; CME Group market data; major exchange funding rate pages.