Resolves to the company - designated as gatekeeper under the EU's Digital Markets Act - that first lawfully fulfils a competitor's request to provide interoperability with their instant messenger.

Companies currently identified as gatekeepers are:

• Alphabet

• Amazon

• Apple

• ByteDance

• Meta

• Microsoft

• Samsung

• Update 2025-02-01 (PST): - Meta will be considered as offering interoperation based on their official statement, even if successful interoperability has not yet been achieved. (AI summary of creator comment)