I've done standups (not scrum, just standups) with up to 16 people and it was quite effective. It just required a concerted effort to keep it short. The nature

I've done standups (not scrum, just standups) with up to 16 people and it was quite effective. It just required a concerted effort to keep it short. The nature of the work probably also helped because tasks took a long time so on any given day only a handful of the people would have substantive updates.