Article 35 of MiFIR provides that CCPs must accept to clear financial instruments on a non-discriminatory and transparent basis, regardless of the trading venue on which the transactions were executed.

CCPs guarantee the successful completion of transactions by interposing themselves between buyer and seller, thereby reducing counterparty risk. For example, LCH SA acts as CCP for Euronext securities and derivatives in France.

The open access principle is based on the idea that market infrastructures must not constitute bottlenecks preventing competition between trading venues. It is established by Articles 35 and 36 of MiFIR.

A central counterparty clearing house (CCP) is an entity that interposes itself between buyer and seller to guarantee the successful completion of transactions, thereby reducing counterparty risk. Example: LCH SA for Euronext securities and derivatives in France.

Market infrastructures include central counterparty clearing houses (CCPs) and central securities depositories (CSDs). CCPs guarantee the successful completion of transactions, while CSDs maintain securities accounts and handle settlement-delivery.

Limitations to open access include operational risks (system incompatibility), legal risks (rule incompatibility), insufficient technical capacity, and threats to economic viability. For example, Article 16 of EMIR concerns minimum capital requirements.

ESMA concluded in April 2016 that open access to exchange-traded derivatives does not create undue risks for European market stability, as the existing safeguards in MiFID II, MiFIR and EMIR were deemed sufficient.

Article 35 of MiFIR provides that CCPs must accept to clear financial instruments on a non-discriminatory and transparent basis, regardless of the trading venue. Article 36 requires trading venues to authorise this access.