The FAQ says:
How many subgroups can I be a member of at one time? 50.
How is it possible to get 51 groups?
https://www.linkedin.com/anet?dispSortAnets=&trk=my_groups-h_gn-settings :
How is it possible to get 51 groups in LinkedIn
linkedinlinkedin-groups
Related Solutions
Yes, that is possible. There is a per-group setting to control the frequency of digest emails. There is an overview for all groups from which it can be set in a batch-like fashion:
Settings (upper right, in pop-up under your name) -> "Email Preferences" -> "Set the frequency of group digest emails".
Change the popup for one or more groups from "Daily digest email" to "Weekly digest email".
It can also be set under each group:
Open a page that is in group context (for example, a discussion in the group or menu "Groups" (in the same row as "Home", "Profile", "Contacts", "Groups", "Jobs", "Inbox", "Companies", "News", and "More") -> "See all" -> click on a group)
Then menu "More..." (in the same row as "Discussions", "Members", "Promotions", "Jobs", "Search") -> "Your Settings"
Under "Contact Settings, Digest Email" change the popup "Delivery Frequency" from "Daily digest email" to "Weekly digest email".
Press button "Save Changes"
And to really cut down on the LinkedIn spam:
- Uncheck the option Send me an email for each new discussion in the same window.
It is possible by using the Advanced search. There you can write some keywords and the related Groups to look. But it is possible only for Groups that you have joined. I'm not aware if there are more possibilities for "Pro" accounts.
Best Answer
It is actually possible to join up to 100 groups on LinkedIn, according to this post from someone who has joined 55 groups. She explains in a video in her post that you can join 50 parent groups and 50 subgroups. I checked a few of the groups in your screenshot, and I found that the "Disruptive I.T." group is actually a subgroup of the "Re-invent I.T." group. You are a member of both groups, and since "Disruptive I.T." is a subgroup, that is how you are a member of more than 50 groups.