The 390 Professional Orders Rule, also known as the "390 Rule," is a regulation established by the Chicago Board Options Exchange (CBOE) for determining whether an options trader qualifies as a "Professional" or "Non-Professional" trader.

The rule is based on the concept of placing an average of 390 option orders per trading day in a calendar month. If a trader meets or exceeds this threshold, they are classified as a "Professional" trader.

This classification can affect the fees and data subscriptions that traders are subject to. Professional traders may have different fee structures and data requirements compared to non-professional traders. You can learn more about this specific rule here.

For further details on option trading at Alpaca, please navigate to our documentation.

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Options trading is not suitable for all investors due to its inherent high risk, which can potentially result in significant losses. Please read Characteristics and Risks of Standardized Options before investing in options.

All investments involve risk and the past performance of a security, or financial product does not guarantee future results or returns. There is no guarantee that any investment strategy will achieve its objectives. Please note that diversification does not assure a profit, or protect against loss. There is always the potential of losing money when you invest in securities, or other financial products. Investors should consider their investment objectives and risks carefully before investing.