This has been known as a possibility for a long time. Some lawyers are just jumping on this later rather than sooner. I don't believe it causes that side effect for most men, though, but it's definitely not rare. I think Risperdal and Invega (its very related "brother" med developed by the same company) increased my breast size. That didn't bother me at all, but hyperprolactinemia did. Also, I believe Invega caused me to develop a benign pituitary microadenoma (prolactinoma). [Uncommon side effect.] I happen to see the latter as a much bigger deal than the breast enlargement, but that's just me. But yes, I am a woman. On the bright side, my pituitary microadenoma did eventually disappear after a number of months off Invega, but I have read that's not always the case. If the pituitary tumor grows very large it does require removal. It can affect things like eyesight, not to mention the usual hyperprolactinemia stuff. Hyperprolactinemia is also a condition that disappeared quickly when I discontinued these two medications. I have never experienced hyperprolactinemia from any other medications, but I've read it is possible (though far less common) as a side effect of many bipolar medications, especially antipsychotics.

Of course I can imagine how distressing it must be for men to develop bigger breasts. I don't mean to minimize that.

Risperdal (risperidone) and Invega (paliperidone) were highly effective antimanics for me and stopped psychosis and extreme agitation. They weren't all bad.