Definition: Open P/L

This is the same concept as when your brokerage platform shows you Open P/L. 

For Positions

This is the sum of all the Legs' Open P/Ls in the Position.

For Legs

If a Leg is still open (non-zero quantity), it is the difference between the cost basis of the open contracts in the Leg and the current market value of those contracts. It does not include commissions/fees, as those are part of Realized P/L.

Quotes are delayed 15 minutes and are sourced from TD Ameritrade.

You can find this number in the "P/L Mode" on Open Positions page.