I've seen some over the years and participated in some. Most of them were Tech companies from back in the early 2000's and the tech boom. Tons of lawsuits were filed relating to IPO's and other activity. I never got anything out of any of them other than 2 and those were just a few cents on the dollar. In the end on those, it wasn't worth the time getting all my paperwork together and submitting it for the little I got back.
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