Hatten, who is currently behind bars for making criminal threats against Smith, alleges Stern tried to kill him seven years ago in a bid to "remove" him from Smith's life.
TMZ.com reports Hatten is seeking $100 million in damages from Stern, claiming he "tried his very best to try and murder plaintiff Hatten and make it look like an accidental death/overdose."
Hatten also alleges "hypnotizing plaintiff's fiance Anna Nicole Smith with Chloral Hydrate."
The lawsuit also names Stern and six other co-defendants, accusing them of slander.
Stern was Smith's partner up until her death of an accidental drug overdose in February.
Lame... so now Howard was trying to kill everyone that came around Anna