Market Manipulation. Search

Closing auction

A closing auction gathers orders into a single batch to set the official closing price. Concentrating the close into an auction improves price formation but also creates one identifiable moment worth attacking.

instruments and markets · updated 2026-09-08

Where does closing auction come up?

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

Enforcement actions involving these techniques

Action Agency Filed Technique Penalty Status
SEC v. Canaccord Genuity LLC (marking the close, 2026) SEC 2026-03-06 Marking The Close , Marking The Open +2 settled
SEC v. Ahmad Haris Tajyar and Eric Leo Marsoubian (marking the close, 2021) SEC 2021-08-13 Marking The Close , Matched Orders +1 $220k settled
SEC v. Andrew J. Kandelapas (marking the close, 2019) SEC 2019-06-21 Marking The Close judgment
SEC v. Lai Guanglin (Alan) (marking the close, 2018) SEC 2018-12-10 Marking The Close , Price Manipulation settled
SEC v. Richard P. Cedrone, Steven R. Ferris and George R. Thoreson (marking the close, 2017) SEC 2017-09-05 Marking The Close $75k judgment

See also

Terms that refer here

Opening auction

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