So-called called "Kat Dennings" was born Katherine Victoria Litwack. It makes one wonder why she'd change her birthname?! Is she ashamed of her parents or heritage? Perhaps it was pressure from a greedy & deceitful manager or studio? The act of changing one's name for perceived greater recognition and possible monetary gain is short-sighted and disrespectful.
She actually did reveal her last name with no issues and explained why she changed it, very simple story she thought Litwack sounded weird in the showbiz with the word wack and used her grandma’s last name who was French and turned it to Dennings ,