UPDATE: Kate's lawyer, Mark Momjian, tells TMZ that Jon's lawsuit is "pathetic" and self-serving.
Attorney Mark Momjian tells TMZ Jon's motives are transparent, saying, "He's never questioned her ability to provide for their children. He's out of the limelight, while 23 million people are watching Kate on 'Dancing with the Stars.'"
Momjian finds it ironic that Kate is effectively the only breadwinner, and when she goes to Hollywood to earn a living he turns around and says she's not in Pennsylvania caring for the kids.
Momjian says the legal docs filed by Jon are "incoherent" and so flawed that he fully expects the judge to throw his petition out ... stat.
Momjian says Jon is out for Jon, adding, "Do I think his motivation is the children's best interest. Squarely no."
AP: READING, Pa. - Jon Gosselin has sued ex-wife Kate for primary custody of their eight children.
The former reality TV star also asked the Berks County Court on Wednesday to review his child support obligation.
Gosselin's attorney, Anthony List, has previously accused Kate Gosselin of neglecting the children because she appears on ABC's "Dancing with the Stars," a charge her attorney rejected as "patently false."
In court papers, Jon Gosselin says his ex-wife "abuses" her authority when it comes to scheduling visits with the kids. He also claims an arbitrator failed to require Kate to provide documentation of the children's expenses.
The Gosselins appeared on the TLC reality show "Jon & Kate Plus 8" until their marriage fell apart last year. They divorced in December.