'Shahs of Sunset' Slams FHM Model -- Mattel Owns 'Barbie', Duh!

"Shahs of Sunset" producers want to school an FHM model on the law -- telling her she has no right to sue over her handle "Persian Barbie" ... because Mattel trademarked the name a looong time ago!!

TMZ broke the story ... Persian model Niki Ghazian (above) accused the reality TV show of illegally using her self-proclaimed moniker, "Persian Barbie" ... for new cast member Lilly Ghalichi.

Now Berne Productions -- a subsidiary of Ryan Seacrest Prod. -- is responding to Niki's cease and desist letter with its own docs claiming she has no stake to the Barbie trademark.

Berne argues the term "Barbie" is 100% owned by Mattel -- and adds, "Any claim that Ms. Ghazian has acquired any property rights to a term that is a basic derivative of "Barbie" (i.e. "Persian Barbie") is unsound and not defensible." Aka ... go kick rocks, Ms. Ghazian.

Berne also claims 'Shahs' isn't violating Mattel's trademark because "Persian Barbie" is merely descriptive of Lilly's rockin' bod.

Exhibit A ...