Interesting, not sure why they need to know?
Check it out:

Jersey City Mayor Steve Fulop (D) is asking gun companies to provide police with information “about their business practices” in order to stay in play for future city firearm contracts.

According to The Wall Street Journal, the information requested includes how gun companies “dispose of old weapons and comply with background check laws, and whether they make semiautomatic rifles… for sale to civilians.” reports that Jersey City also wants to know what gun companies do with police trade-ins – whether those trade-ins are resold to the public.