Margin

Margin is collateral posted against a position. Because margin requirements are calculated from marked prices, a manipulated price can force genuine participants to post cash or liquidate.

instruments and markets · updated 2026-10-16

Where does margin come up?

This term is used in the following manipulation techniques, each explained in full on its own page.

• Marking the close — Marking the close is trading in the final minutes of a session specifically to move the closing price, which is the price that sets portfolio valuations, margin calls, index levels and derivative settlements.
• Engineered short squeeze — An engineered short squeeze is deliberately acquiring the tradable supply of a security and withdrawing it from the lending market, so that short sellers who must cover cannot find stock and are forced to buy at the engineer's price.

Enforcement actions involving these techniques

See also

• Clearing house — A clearing house interposes itself between buyer and seller, guaranteeing performance and collecting margin. Its margin calls are …
• Mark to market — Marking to market is valuing a position at current market prices. Because it converts a price into reported profit, collateral and…

Terms that refer here

Clearing house

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