The NYSE Arca equities platform provides for three types of participants: Market Makers, Lead Market Makers and Order Routing ETP Holders.
Market Makers
A Market Maker is an ETP holder or firm that has registered with NYSE Euronext to trade securities. Market Makers are obligated to maintain continuous two-sided Q Orders in all registered securities.
Lead Market Makers
Any registered Market Maker may apply to become a Lead Market Maker (LMM). LMMs operate off-the-exchange trading with more stringent quoting obligations and in some cases, participation guarantees. LMMs must maintain specified cash or liquid assets based upon the number of issues traded.
NYSE Arca Equity Lead Market Making Firms: