This is not a lawsuit or countersuit. Instead, it is a Rule 37 Motion for Sanctions regarding discovery. (See Fed. R. Civ. P. 37.) The claims are an awful lot like a Rule 11 motion, though. I would think they'd try to move for sanctions under Fed. R. Civ. P. 11(b)(3) (stating that the claims have no evidentiary support). Maybe Mr. Beckerman could comment on whether he's been served under Rule 11(c)(2) prior to filing with the court?
The plus side is that Plaintiffs are moving for dismissal, but they're trying to get the court to order it, probably so that they won't have to pay attorney's fees.