When adopted in 2014, the definition covered an investment firm that does this on an organised, frequent, systematic and substantial basis1. The ESMA version limits own-account dealing to equity instruments and also covers a firm that opts in to the SI status2. Because an SI takes on trades outside trading venues, it is distinct from the operator of a trading venue (a regulated market, an MTF or an OTF). The article that covers this term explains the details.
Systematic internaliser
- Japanese
- システマティック・インターナライザー
- Also known as
- SI
- Last reviewed
- October 3, 2026
This is a draft, shown for review before publication.
A systematic internaliser (SI) is a MiFID II category of investment firm that executes client orders on own account outside trading venues, without operating a multilateral system.