Hi,

Anytime you see "SNC" like that, it's referring to a protected, but out of box script controlled by ServiceNow. In this case, it's a script include that we simply don't have access to and from the context here, it's utilizing that to quickly check and see if the user has the appropriate permission allowed to grant access to this group. So it's basically a short-cut crafted by ServiceNow to check. There really isn't much other documentation on this as it's controlled by ServiceNow, so my apologies for not being able to provide more. This question was also asked almost a year ago and unfortunately, there isn't much else to provide at this time. https://community.servicenow.com/community?id=community_question&sys_id=96cca458dbbc9c10d58ea345ca96...

If you want to make adjustments, you can create a new "create" ACL for the sys_user_grmember table to accomplish what you need as that would leave this unaffected and be in addition to instead of replacing.

Please mark reply as Helpful/Correct, if applicable. Thanks!