The New York Stock Exchange LLC (NYSE) and NYSE Alternext US LLC (formerly known as the American Stock Exchange) filed tandem rule proposals to reflect that Designated Market Makers (DMMs) on each exchange will no longer have agency responsibilities for orders entered on the exchanges’ marketplaces. The changes became necessary after the NYSE recently filed a series of rule changes to replace specialists with DMMs. Because the DMM no longer functions as agent for orders displayed on the exchange’s book in the current market structure, the proposed filings were introduced to amend legacy rules that retain the concept of the exchange market maker as agent.  

http://www.sec.gov/rules/sro/nyse/2009/34-59415.pdf  

http://www.sec.gov/rules/sro/nysealtr/2009/34-59416.pdf