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What Are TD Ameritrade’s Requirements on Short Selling?
In order to short sell on TD Ameritrade, you must have a margin-enabled, non-retirement account with at least $2,000 in marginable equity.
The equity required to maintain your short position may vary based on the market price of the security you shorted, and if the short position moves against you your account could face a margin call, requiring you to deposit additional funds. TD Ameritrade must also be able to locate shares for you to borrow before you can short a stock. They do not allow shorting of OTC stocks (i.e. penny stocks).
Si cumplis esos requisitos y no funca tendrías que enviarles un mensaje x el Message Center consultando.