A round lot of a stock trade is defined in the securities industry as how many shares?

A round lot of a stock trade is defined as 100 shares in the securities industry. This standard was established to provide consistency in trading practices, allowing for easier processing and execution of trades. Round lots are commonly used for large transactions, making them more straightforward to handle for both brokers and investors.

In contrast, trades involving fewer than 100 shares are considered odd lots, which may have different settlement rules and often carry different transaction costs. Understanding the concept of round lots is important for traders, as it influences the liquidity of the market and how transactions are processed.