Meta details WhatsApp and Messenger interoperability under the EU's DMA, saying third parties must use Signal's protocol, which Meta already uses for encryption
Context & Ripple Effects
Meta's DMA preparation had already been framed around an opt-in experience and a separate inbox for outside conversations in Meta's earlier interoperability design. That approach makes interoperability a controlled extension of the messaging products rather than a wholesale merger of user inboxes.
Later coverage added a staged path for group chats and calling beyond initial third-party messaging, while a subsequent planned European launch named initial partner apps for the first integrations. The protocol requirement is therefore a key implementation choice in a longer compliance rollout.
First-order effects
- Third-party messaging services seeking access to WhatsApp or Messenger in the EU must implement Signal's protocol, making compatible end-to-end encryption a practical entry requirement.
- Meta retains significant control over the interoperability boundary: outside chats must meet its chosen security standard rather than connecting through any protocol of their choice.
Second-order effects
- Potential partners face added engineering and compliance work to support the required protocol, which may narrow participation to services able to absorb that integration cost.
- The separate, opt-in inbox model limits immediate disruption to Meta's core messaging experience while giving users a managed route to communicate across services.
Third-order effects
- If this model persists, DMA interoperability could develop around platform-specified technical and security conditions, shifting competition toward who can meet those interfaces rather than simply who can offer a messaging app.
- The later expansion plans for groups and calls suggest that interoperability obligations may broaden feature by feature, increasing scrutiny of whether implementation choices enable meaningful access or merely formal compliance.
The trend: EU platform regulation is pushing dominant messaging services toward controlled interoperability, with technical standards becoming a central lever of access and competition.