Preface with typical IANAL and whatnot.
But with Formlabs not actually shipping anything yet, the best they can do is a cease and desist, right? That could screw them, but as others have mentioned they can seemingly get around the unexpired patents.
Litigation costs are another issue of course. It could easily kill the kickstarter-sourced funding.
The "funny" thing about HIV is that, if it killed instantly (days or weeks) people would be MUCH more apt to be careful and NOT GET IT it because it's completely preventable aside from rape, unknowingly getting it through blood transfusions (rare) etc.