Bucketing

What Does Bucketing Mean?
A situation where, in an attempt to make a short-term profit, a broker confirms an order to a client without actually executing it. A brokerage which engages in unscrupulous activities, such as bucketing, is often referred to as a bucket shop.

Investopedia explains Bucketing
If the eventual price that the order is executed at is higher than the price available when the order was submitted, the customer simply pays the higher price. On the other hand, if the execution price is lower than the price available when the order was submitted, the customer pays the higher price and the brokerage firm pockets the difference