Filial rating, also known as generation rating, is a system used to classify Bengal cats based on their level of wild ancestry. The system is based on the number of generations removed from the wild ancestor, the Asian leopard cat (ALC).
Here is a general explanation of the filial rating system for Bengal cats:
F1: First generation Bengal cats are the offspring of an ALC and a domestic cat. They are considered the closest to the wild ancestor and are highly sought after. They are considered the most wild-looking and have the most distinct spots and rosettes.
F2: Second generation Bengals are the offspring of an F1 Bengal and a domestic cat. They are considered less wild-looking than F1s, but still have distinct spots and rosettes.
F3: Third generation Bengals are the offspring of an F2 Bengal and a domestic cat. They are considered less wild-looking than F2s and may have more diffuse spots and rosettes.
F4 and beyond: Cats of fourth generation and beyond are considered more domestic-looking and may have less distinct spots and rosettes.
It's worth noting that this system is not universally used and different catteries or organizations may use slightly different definitions. Additionally, the Filial rating is not only based on looks but also on behavior and characteristics.