According to the source, a social post claims MicroStrategy holds 63% of the BTC held by corporate Bitcoin treasuries, but no primary dataset is cited and this proportion cannot be independently verified here. Source: X post dated 2025-09-20. Verified filings show MicroStrategy is the largest corporate holder of BTC, with holdings exceeding 200,000 BTC in 2024. Source: MicroStrategy investor relations and 2024 SEC Form 10-Q filings. Independent trackers reported total public-company BTC treasuries in the low hundreds of thousands of BTC in 2024, implying MicroStrategy’s share is dominant but date- and methodology-dependent. Source: BitcoinTreasuries.net by BuyBitcoinWorldwide and underlying company reports. For trading, concentration risk can tighten circulating supply and amplify BTC volatility, while MSTR has historically traded as a high-beta proxy to BTC that traders use for directional exposure or hedging. Source: Nasdaq historical price data for MSTR and Coin Metrics BTC price series (2023–2024). Actionables: confirm the latest MicroStrategy BTC balance via its investor updates, cross-check aggregate corporate holdings from primary filings, and monitor US spot BTC ETF net flows to gauge incremental demand that can offset or compound treasury concentration. Sources: MicroStrategy investor relations; SEC EDGAR; iShares Bitcoin Trust and Fidelity Wise Origin Bitcoin Fund daily flow disclosures.