If your account does not satisfy its initial and maintenance margin requirements at the end of the day, you will receive a margin call the following morning. We will contact you and advise you of the call amount that you will need to satisfy either by depositing new funds or liquidating some or all of your positions to reduce your margin requirement sufficiently.

Furthermore, we may contact you prior to the end of the day and ask you to liquidate your positions immediately in the event that your account equity is materially below your maintenance requirement. Furthermore, although we will make every effort to contact you so that you can determine how to best resolve your margin call, we reserve the right to liquidate your holdings in the event we cannot get ahold of you and your account equity is in danger of turning negative.

Please visit Alpaca Docs to read more.

Margin & Short Selling - Documentation | Alpaca
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