https://www.techdirt.com/articles/20190228/17170141697/blackberry-continues-shameful-descent-into-patent-trolling-suing-twitter.shtml

BlackBerry (under its original name RIM) was always a bit of a patent troll. While it did have some early innovations in the mobile device space, and had popular actual products on the market for a while, it always had a habit of vindictively suing any company that seemed to be offering anything remotely similar to its products. Perhaps the company should have spent more time focused on its actual product rather than suing for patent infringement. Otherwise, its market share chart wouldn't have looked like this, courtesy of Statista:

However, now that its business of selling actual products has bottomed out, it's gone back to its earlier focus of suing totally random companies for doing fairly obvious things, and claiming that they violate Blackberry's patents. Last year, we covered its silly lawsuit against Facebook that only got them hit with an equally silly countersuit from Facebook.