There's limited information at this point -- but what we know is Kim, who was an executive producer on his 2023 documentary film "Milli Vanilli" -- filed the divorce docs in L.A. County Superior Court.

Kim is also listed as Fab's manager on IMDB, a 1997 L.A. Times article refers to her as his best friend.

Here's another plot twist -- less than 3 months ago, Fab told People magazine said he's been living in Amsterdam with his partner Tessa van der Steen and their 4 kids -- ranging from ages 2 to 10.

That news wasn't all that shocking, at the time, because no one knew he'd been married.

So, it's possible Fab and Kim separated ages ago, and she's just now getting around to filing divorce paperwork.

Nonetheless, Fab may still be on decent terms with Kim ... they posed together last June in NYC during the Tribeca Film Festival -- where he also posed for pics with Tessa.

Busy guy!