Until around 10 years ago, Nosler bought in all the cases it sold bearing the 'Nosler' headstamp. Norma supplied most (all?), and it was generally very good quality indeed. (As it should have been given the asking price for this company's 'Custom Brass'.) Then Nosler bought the Silver State Armory outfit, a small manufacturer whose reputation was good for brass such as the 6.8mm Rem SPC which was 'very in' at the time. IIRC, SSA specialised in smaller cases for US AR-15 shooters.
This gave Nosler an in-house case manufacturing facility and it switched the 'Nosler Custom' brand to its own cases wherever possible, only contracting out to Norma or whoever for those types with limited demand.
My impression from forum comments etc is that quality and customer satisfaction for the in-house cases went downhill subsequently, especially as Nosler seems to still regard its products as premium grade and prices them accordingly.