What happens to Strategy (MSTR) if Bitcoin drops 50%?

No claim in Strategy's stack can be called because the Bitcoin price fell. None of the active instruments on record carries a price gate, an escalator trigger or a holder put date: the convertible notes convert at fixed prices set in their indentures, and the remaining secured borrowing that was Bitcoin-collateralized was prepaid in full and retired in March 2023.

The preferred dividends keep accruing whatever the price does. STRK, STRF and STRC are cumulative by their filed terms, so an unpaid dividend is not forgiven; it accrues into the liquidation preference and enters the claims stack there. A lower Bitcoin price does not slow that and does not trigger it.

What a drawdown changes is the arithmetic, not the obligations. The claims above are fixed in dollars, so as the price falls the same claim consumes more of the reserve, Senior Claims % rises and CEBE per share falls. Nothing is called and nothing is forced; the common's share of the Bitcoin simply gets smaller.