Greeks

FLEX Options

By Ryan Silk & Lawrence Polatchek · Reviewed April 2026 · Options Trading Glossary

Customizable exchange-traded option contracts

What is FLEX Options?

FLEX Options Customizable exchange-traded options that allow traders to specify non-standard terms including strike price, expiration date, exercise style, and settlement type. FLEX options are cleared through the OCC, combining the customization of OTC options with the credit safety of exchange-traded products.

Complete Definition

Customizable exchange-traded options that allow traders to specify non-standard terms including strike price, expiration date, exercise style, and settlement type. FLEX options are cleared through the OCC, combining the customization of OTC options with the credit safety of exchange-traded products.

Related Terms

Options Clearing Corporation Exchange Traded European Option American Option

Written by

ApexVol Research Team

Quantitative options research

All calculations use live ORATS institutional data — the same source used by professional volatility desks.

Technical reviewer

Ryan Silk, ApexVol Founder

Reviewed for technical accuracy

10+ years trading options. Built ApexVol's pricing engine, Greeks model, and IV-rank methodology.

This guide is updated as market conditions and ORATS data change. Last revised 2026-05-12. How we research →

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