Multiple Listing Service

A multiple listing service (MLS, also multiple listing system or multiple listings service) is a suite of services that enable real estate brokers to establish contractual offers of compensation (among brokers), facilitates cooperation with other broker participants, accumulates and disseminates information to enable appraisals, and is a facility for the orderly correlation and dissemination of listing information to better serve broker's clients, customers and the public. A multiple listing service's database and software is used by real estate brokers in real estate (or aircraft broker in other industries for example), representing sellers under a listing contract to widely share information about properties with other brokers who may represent potential buyers or wish to cooperate with a seller's broker in finding a buyer for the property or asset. The listing data stored in a multiple listing service's database is the proprietary information of the broker who has obtained a listing agreement with a property's seller.

According to the U.S. National Association of Realtors:

In the late 1800s, real estate brokers regularly gathered at the offices of their local associations to share information about properties they were trying to sell. They agreed to compensate other brokers who helped sell those properties, and the first MLS was born, based on a fundamental principle that's unique to organized real estate: Help me sell my inventory and I'll help you sell yours.

The term "MLS" is considered generic in the United States and cannot be trademarked or branded. There is no single authoritative MLS and no universal data format. However, there is a data standard for MLS systems—the Real Estate Transaction Standard—which is being deployed across MLS solutions in North America. Local and private databases use XML-based data feeds to generate and update listings. Listings disseminated through MLS may be controlled by a single association of realtors or groupings of associations which represent all brokers within a given community or area.

The primary purpose of an MLS is to provide a facility to publish a "unilateral offer of compensation" by a listing broker, to other broker participants in that MLS. In other words, the commission rate that is offered by the listing broker is published within the MLS to other cooperating brokers. This offer of compensation is considered a contractual obligation, however it can be negotiated between the listing broker and the broker representing the buyer. Since the commission for a transaction as well as the property features are contained in the MLS system, it is in the best interests of the broker participants (and thereby the public) to maintain accurate and timely data.

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