If one of the top five clearing members were to default, CCPs and other members would be able to successfully execute default management processes, even in a multi-CCP setting where operational frictions and capacity constraints are most likely to surface — but with AML/KYC checks as a key barrier to client porting, particularly where there is no pre-arranged backup clearing member. 

A more aggregated or consolidated approach to porting information, rather than the client-by-client basis many CCPs currently use, could help ease those strains and support faster processing in the short windows that follow a real default, according to a Bank of England-published review of the latest global default simulation exercise.

That was the headline finding from participants, alongside a broader call for greater harmonisation: more consistent communication conventions, common data standards, and faster, more automated tools to support processing under stressed conditions.

The Global International Default Simulation (CIDS) exercise, coordinated by industry body CCP Global, was carried out in November 2025 and drew 38 CCPs, clearing members, clients and regulators, up from 33 participants in the previous run in November 2023. Regulatory oversight was led by a group of five CCP authorities, known as the Lead Authorities.  

Focus areas

New for 2025 was a “Client Porting” module, testing the transfer of a defaulted member’s client positions to a surviving clearing member — generally the preferred outcome over liquidation, since it preserves client assets and market access.

Across the exercise’s other focus areas — auction file dissemination, bidding and post-auction feedback — participants raised closely related concerns: a lack of common standards, fragmented communication, and heavy reliance on manual processes such as email. On auction files and bidding, they wanted standardised formats, ISIN and trade-identifier enrichment, consistent sign conventions, and a shift from email towards real-time web portals. On feedback, members wanted faster and more consistent responses, especially when a bid or porting request was rejected.

In response, the Lead Authorities set out two priorities. First, inconsistent procedures and communication conventions across CCPs risk weaker auction outcomes and hidden costs for members; they want industry-led progress, including a voluntary auction file standard, wider use of portals, and less reliance on email. Second, future CIDS exercises should test porting more realistically to stay proportionate to a live default, with clearer guidance under consideration alongside a possible voluntary “market stress overlay” module testing bids under a shared cross-CCP stress scenario.

The next CIDS exercise is expected in 2027.