Gemini has controls in place to protect customers from fat-finger mistakes as well as to ensure they do not get filled too far away from the current price during times of low liquidity. 

Please take note that none of these controls apply to stop-limit orders. Below is a summary of the controls.

• If the buy side of an order book is empty, it is not possible to submit buy orders that would fill immediately (either through a market order or a limit order with a limit higher than the current best ask).
• If the sell side of an order book is empty, it is not possible to submit sell orders that would fill immediately (either through a market order or a limit order with a limit lower than the current best bid).
• If the spread between the best bid and best ask is large such that both best bid and best ask are at least 5% away from the mid price, it will not be possible to send buy or sell orders that would fill immediately (either through a market order or a limit order).
• Limit GTC and Limit IOC orders with a limit of more than 5% through the order book would only be filled for a quantity up to 5% away from the mid price. Any remaining quantity would be canceled. 
• Limit FOK orders with a limit of more than 5% through the book would be cancelled if they could not be filled within 5% of the current mid price. 
• A market order that would get filled more than 5% from the current mid price will be rejected, even if some of its quantity could be filled within 5%.
  • For example: the threshold is 5%, when a user places a market order to buy 10,000 USD worth of WIF in the WIF/USD market. The current ask price is 1.05 USD, bid price is 1.048 USD. If the system determines that the final execution price would be 1.2 USD. As for (1.2 -1.049)/1.049=14.39%>5%, the market order will be rejected as it is more than 5% from the current mid price (1.049 USD)