Yikes! Yeah, I’m not seeing anything in the API docs even tho I thought you could… instead I guess what I was thinking of was the webhook for when someone joins. 

If memory serves me correctly, Groups were built and released during a pre-Gainsight era of Insided when new modules (Groups, Product Updates, Ideas 2.0) were being added, but without complete parity to other parts of the platform. Thankfully that hasn’t been the case for awhile (and they’ve recently fixed a few examples of this for Ideas), but Groups API operations appear to still be a major gap.

All that said… I bet support could help with a hidden API call. I’d have to think it exists and just isn’t documented. But maybe not.  

If you need an alternative…

You could create a regular community category and custom role for partners, setting the permissions accordingly. Then you could backfill (and automate going forward) partner users to get the custom role. 

The downside of this (and perhaps why you were going towards a group) is that you lose the auto-subscribe to new posts that comes when someone joins a group. Each user would need to manually subscribe to the community category forum (and there’s not a way to do that for them)

OR… if the group is mostly to share content with them, you could do a combination of the category and a custom page. The custom page could leverage widgets for a better UX and create a partner launchpad of sorts. The category would be the actual place where you would publish the content, but could be mostly hidden/deprioritized in navigation.