You may have noticed that group notifications are cluttering up your News Feed on Facebook even though you are not subscribed to group updates. 
Here is how you can fix it.
1. Hover or roll your mouse over the post. In the right hand corner you should notice a blue down pointing arrow pop up. Click on the blue down pointing arrow and click on Hide.
2. Clicking on Hide will hide the single post. To hide ALL posts from the group on your News Feed click on the Hide all stories from link. See picture below. 
3. Now all stories from that group should be hidden from your News Feed. You can still view the stories or posts by going directly into the group. To manage your hidden items scroll to the top of your News Feed and click on the pencil next to News Feed to Edit your settings.
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