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How markets work

How a trade settles, how short selling works, and what happens when an index changes its members.

All How options are priced Option expiration and assignment Earnings Mergers, acquisitions and spin-offs Reading SEC filings How markets work The economy and the Fed Other markets that move stocks Risk and position sizing Who owns what

No. 003 Mon 19 Oct 2026

How markets work · History

In the 1987 crash, four sellers made 14% of the stock sales