An attorney says that for EB-1 the USCIS criterion regarding the “critical role” is ideally satisfied by a letter of collaboration from a U.S. government agency. It’s clear that this is physically unattainable in most cases. But she didn’t propose any other options. How else can this requirement be met — who has gone through what?
Detailed analysis of the topic: Critical role: breakdown of the criterion
critical role != leading role — they’re different things. A critical role is about the fact that you’ve made a significant contribution to the company or a specific project, while a leading role is when you need to demonstrate hierarchy and your place in it. So you can be a senior developer without managerial responsibilities and prove a critical role by the projects you worked on and by showing that they wouldn’t have happened without you. Also, letters from the US carry more weight here than those from foreign companies — there you need to show the candidate’s value specifically for the American market; that’s a separate factor.