[SideburnsOfDoom]

> just let the system in possession of data send with the event only the part of data it owns (i.e. something in between fat and thin).

Is that really different from a fat event?

[ivan_gammel]

Yes. The owned part of saga can be as small as an acknowledgment of something that happened. Basically, you do not create the pattern of fat event in your architecture and then stick to it, instead you send both fat, thin and in between depending on context.