The Armand Nicolet AN2846-9 is essentially an ETA 2846 with a custom Armand Nicolet branded rotor.
ETA 2846 Base
The Armand Nicolet AN2846-9 is essentially an ETA 2846 with a custom Armand Nicolet branded rotor – hence the 2846 in the caliber number.The base 2846 movements typically have 17 or 21 jewels, the AN has 23.
Although marketing material makes it sound like this movement is proprietary to Armand Nicolet, they left the ETA logo and 2846 caliber number etched into the plate below the balance wheel.
The ETA 2846 was discontinued circa 2006. It’s likely that AN came across new old stock movements and customized and regulated them in-house. AN’s 2015 catalog mentions some of their other calibers being sourced NOS and refinished in-house. For example, they acquired a caliber UT 600 that was originally produced in 1957, and after modifying and refinishing it, the movement became caliber AN0711A.