Magnetar Financial LLC 4

What Happened
Magnetar Financial LLC, reported as a 10% owner of CoreWeave, had multiple short derivative positions tied to CoreWeave Class A common stock expire unexercised on March 20, 2026. The aggregated amount shown in the filing is 4,837,526 shares disposed by expiration; all expirations generated $0 proceeds because the options expired worthless (unexercised).

Key Details

• Transaction date: March 20, 2026; Transaction code: "E" (expiration of short derivative position). Report filed March 20, 2026 (appears timely).
• Total expired/disposed: 4,837,526 underlying shares; reported value: $0 (options expired unexercised).
• Reason: Footnote F1 states these were part of a collar (call and put entered Aug 15, 2025); both options expired unexercised because CoreWeave's closing price on Mar 20, 2026 was between the call and put strike prices.
• Holdings structure: The positions are held across Magnetar-managed funds (see F2–F12). Magnetar entities disclaim direct beneficial ownership except to the extent of pecuniary interest.
• Shares owned after transaction: Not specified in the provided extract of this filing.
• Note: These were derivative expirations (no open-market sale); not an executive cash sale or purchase.

Context
This filing documents institutional derivative expirations rather than a cash sale or purchase by a company insider. For retail investors, expirations for no value simply reflect option contracts lapsing — they do not by themselves indicate a buy/sell signal from company insiders. Magnetar here acts as an investment adviser/ fund group (10% owner), not an individual executive.