As defined by the U.S. Supreme Court a Bucket shop is "[a]n establishment, nominally for the transaction of a stock exchange business, or business of similar character, but really for the registration of bets, or wagers, usually for small amounts, on the rise or fall of the prices of stocks, grain, oil, etc., there being no transfer or delivery of the stock or commodities nominally dealt in." People often mistakenly interchange the words bucket shop and boiler room

Boiler room (business)

In business, the term boiler room refers to a busy centre of activity, often selling questionable goods by telephone. It typically refers to a room where salesmen work using unfair, dishonest sales tactics, sometimes selling penny stock or committing outright stock fraud...

, but there is actually a significant difference.