Brokers and MLSs don’t speak the same lanugage. In this article, Sam DeBord decodes the translucent industry lingo surrounding MLS consolidation.

  • Real estate apps and data don't function seamlessly across MLS, broker and vendor tools — there are concrete technical reasons.
  • Brokers need to understand the issues that keep them from leveraging MLS data fully.
  • MLSs need to adopt new technology standards and more responsive decision making processes to support brokers.

Brokers and multiple listing services don’t always speak the same language. Part 1 of this series focused on decoding the translucent industry lingo that surrounds MLS consolidation. Part 2 will focus on the inability of brokers and MLSs to come together on technology innovation. 

Brokers feel their technology is stymied by MLS bureaucracy. Most of the industry, though, doesn’t understand how the entire MLS system works, brokers included.

There are reasons you can’t:

  • Update a listing from your smartphone app
  • Create a client’s saved listing search criteria and have it shared with every tool you use
  • Pull listings instantly from your MLS to use in a great new tech product that you bought at a trade show
  • Build an application within your brokerage that inputs your listing into three MLSs at once

The reasons often have to do with how your data is organized and shared at the MLS level.

Commit 10 minutes to understanding how the system really works. There’s no bridging the MLS-broker divide without common understanding, and I promise there’s something here you’ll learn by the end. (Apologies to technologists for some oversimplifications — things like APIs are difficult to visualize.) 

‘The back end’ — Primary MLS database where listings are stored

Think of the MLS back end as a desktop computer tower. 

Your MLS listing data is stored here. You might also store more data here like customer info, their saved searches, prospects, etc. This database is probably managed by your primary MLS vendor, the most well-known of which are:

  • CoreLogic
  • FBS
  • Black Knight
  • Rapattoni
  • SEI (Systems Engineering Inc.)
  • Stratus
  • dynaConnections

The database can also be managed independently by a technology-savvy MLS, a topic for another day. 

‘The front end’ — Primary MLS input application

Think of the MLS front end as the monitor/keyboard/mouse.  

You use them to see what’s in the desktop computer database, and enter more information into the database back end. The same technology vendors that provide the back ends provide most of the front ends that agents and brokers use: Paragon (Black Knight), flexmls (FBS), Matrix (CoreLogic) etc.

For most MLSs, this front end is the only way to input or change listings.

What’s a vendor?

Any technology company whose tools interact with brokers’ data is a vendor:

  • MLS listing input application vendor
  • Showing scheduler in the MLS dashboard vendor
  • Broker’s transaction management software vendor
  • Agent’s website vendor

Sometimes a broker’s staff build their own technology — the broker is its own vendor.

Does your MLS database computer have the right ports? 

Picture the back of a modern desktop computer. There are familiar ports for your devices: standard monitor ports, USB, HDMI, etc. There are unlimited devices you can plug in to these ports: inputs like microphones and webcams; outputs like speakers and printers. 

The connectors on the back of MLS computers, though, look more like this:  

bizarro cable plug

Bizarro Connector — RETS

These bizarre-looking plugs are proprietary to the MLS and real estate. These are the only ports on the traditional MLS computer. No one uses them in any other industry.

They work fine, but they’re dated — Bizarro connector technology isn’t being updated over time to stay current with the rest of the world. Even with an adapter, new technology is limited to what the Bizarro connector can deliver: static listing data sets.

Bizarros work on a technology called RETS (Real Estate Transaction Standard) that was developed 20 years ago by the National Association of Realtors (NAR). It’s essentially written in Latin, a dead language that’s no longer expanding its vocabulary. Implementing it takes more time and training compared to newer technologies. That can be expensive for new tech companies who’d rather work with more modern systems, so many shy away from the MLS world.  

Modern USB Cable — Web API

Industry veteran tech companies have built inputs and outputs —keyboards and printers — based on the MLS’s Bizarro connectors. So although this technology’s long-term use is limited, it still dominates the MLS computer space today.

There’s a new connector available that now gives us more options than the RETS Bizarro. It’s the MLS’s USB cable, called the RESO Web API (more later). 

Is your MLS organizing your data?

Agents and brokers input their listing data into the MLS computer back end. Each MLS is in its own location and has its own rules for listing input. This runs behind the scenes but is vastly important.

In SpeedMLS, when users input a listing, they must include a price, and it has to be in round dollars. A popup box will block the input if the user doesn’t follow the rules. These are SpeedMLS’s “business rules.” A user inputs $195,000 as a price in the SpeedMLS computer. It’s stored in a field with a description of “ListPrice.” This keeps it organized and easy to find later.

ChetMLS, on the other hand, allows users to put anything into the price field when they list. So some entries are blank, some say “Call for details,” and one even has $0.37 as a home’s list price. ChetMLS saves this data on its MLS computer in a price field labeled “GitSome.”

There are hundred of more fields for listings: “Agent,” “Brokerage,” “ShowingRestrictions” in SpeedMLS correlate to “WhoDat,” “DaMan” and “Haterzzz” in ChetMLS.

SpeedMLS has all of its business rules written down for clarity. ChetMLS doesn’t. It’s not as if anyone outside of ChetMLS’s island needs to see this data anyway. 

Want to share data? 

You can see how differently the simplest data — a list price — could look in these two scenarios. Now imagine being a broker, or a broker’s technology vendor, trying to work in these marketplaces. Your technology tools have no idea what to expect when they plug into one of these MLSs. 

Buy a comparative market analysis (CMA) product at a trade show for your company that already works in SpeedMLS’s market. It might take months for the CMA company to figure out how to work with ChetMLS’s data. 

You want to pull listings from both MLSs? If your brokerage technology tools have not already dreamed up and built out a scenario where they understand “depends on your buyer’s down payment” is supposed to be a price described in its data field as “GitSome,” you’ve got a long road ahead. There are hundreds of other data fields, and this is just two MLSs. 

Want to share a listing between two MLSs? 

Imagine trying to get ChetMLS’s listing into SpeedMLS’s database. It’s one property that’s attractive to both of their local geographies.

But every technology company is going to have to dig through ChetMLS’s hard drive and figure out how it organizes (or doesn’t organize) its data first. There’s no easy way to share it across MLSs.

Standards are sexy 

MLS data was originally created and stored differently across geographies, without a unifying standard. It’s now in the process of standardizing, and many MLSs are leading the charge, but we have a long way to go.

When the data follows a standard format (called the Data Dictionary), the business rules are clear, and the data is open to modern API sharing, technology moves faster. 

Standards make everyone’s data more powerful, accelerate the productivity of their technology tools and make their users look good.

Upgrading your connector cables

New technology can replace the Bizarro connector system. The web API from the Real Estate Standards Organization (RESO) is real estate’s version of the USB cable.

It’s straightforward for any vendor to pick up and use. It can copy an MLS database for a broker or vendor like the Bizarro connector does, but it does much more.

It can transmit broader data than just listing data: your clients, their saved searches, analytics for data usage and more are exchanged freely between faster, lighter mobile tools. 

It can plug into smartphones, watches, vehicles and gadgets that no one in the Bizarro connector world has yet seen. Everyone building a new tool understands the USB API technology.  

So MLSs need a USB port on their computers. Technology companies in the industry should be trying out all the features of the new USB connection. They may continue doing their work via Bizarro connectors right now, but the MLS needs to give them the option to start working in what will be the standard way to deliver data in the future. 

Brokers: ‘I’m ready to use my sexy standardized data!’ 

Not so fast: MLSs have to know how to install USB ports, and their brokers and vendors have to help. Some back-end MLS servicers can provide a USB port with Data Dictionary feeds for multiple MLSs: CoreLogic’s Trestle, FBS’s Spark API, Black Knight’s Property Information Central (PIC) and more.

MLSs with very little staff support may not yet understand this. They have to get the USB port first, by asking their MLS software provider for API access, before their brokers and vendors can use it.  

Brokers: ‘Now I’m really ready!’

There’s more to it. You can’t plug in that USB cable until the MLS gives you permission. You want to pull the data, so you’ve got to sign a licensing agreement with the MLS.  

  1. The broker or technology vendor submits an application for a data license.
  2. It goes to the MLS, which goes to a technology committee, which meets quarterly.
  3. If approved, it goes to the board of directors which meets bi-monthly.
  4. The board asks the tech vendor to demonstrate how it will use the data. The tech vendor explains that they can’t show that without having the data to work with. 
  5. One year later after much wrangling, the vendor might have the data and technology tools up and running. 

This isn’t the situation at all MLSs, but it’s a widespread condition.

What can I do in my market? 

Brokers need to talk to their MLS administrators and vendors to explain what they need and help them find the technical support to make it happen. 

  • Clean up your MLS back end: Get Data Dictionary and API certified. Get your business rules documented. If you don’t know how, call RESO.
  • Open up your front end and back end: This doesn’t just mean adopting RESO standards (as NAR policy requires that Realtor MLSs do) and getting RESO certified. It means talking to your back-end vendor and helping them get your USB API set up so brokers can actually plug in to the data in production — within their live products. 
  • Create a safe testing ground: Let vendors test new interfaces in a development environment with MLS data. Be open to alternative front ends for searching and inputting listings.
  • Streamline your decision-making processes: All data access decisions don’t have to be made by committee. The MLS isn’t the same as an association, and it doesn’t need to be run like one. There are standard data licenses available that fill most needs, and most vendors working with brokers are known entities in the industry.
  • Don’t reinvent the wheel every time you get an application: Put decision makers on staff who can interpret policy and give them the authority to make data access decisions in short order.  
  • Engage your board of directors in the discovery process: Ask where they’d like to be five years from now. They supply the what and the how, and the organizational changes immediately have organic buy-in. If you need a roadmap, call Tim Dain at MARIS.

Free the data 

We devalue our data when members can’t access it. They’ll look elsewhere if it takes them a year to get it.  

Protecting sensitive client data is essential, but let’s not kid ourselves: most of our listing data has already flown the coop. It’s been aggregated and leveraged by reputable tech companies that grew tired of waiting for all MLSs to reach standards of practice.  

It’s being packaged and resold in darker markets by those who simply have the wherewithal to scrape one agent’s website in every MLS market or even just a few big broker VOW sites.

Our brokers could have faster, more accurate, easier access to create value with this data if our MLS structures allow them to flexibly access it. 

To make this progress happen, we have to agree that there is no “them.” We all need to do our part.

P.S. If I broke my promise, and you didn’t learn anything, then I owe you a drink and a longer conversation.

Advanced classes will be led by all comers in the lobby at Inman Connect New York: 

  • Web API 503: Yes, it replicates: satisfying listing data and delving into customer data, solving some Upstream-like concerns.
  • Replication 429: Copying the entire database can be expensive: why MLSs encourage some vendors to use lighter live queries.
  • MLS Governance 404: The big picture: your brokers request a review of CMLS best practices and NAR’s MLS policy on a regular basis.
  • Whose Database Is It Anyway 401: Front end of choice and interoperability: standards expansion will break the industry free from locked-in solutions.
  • (Dis)Organized Industry 403: Identifying agents and companies in data: how politics and governance can make a remarkably straightforward task unbelievably difficult.
  • Payload/Permissioning Hackathon: Every MLS and software exec in one room: Create an industry standard for IDX, VOW and Broker Back Office licensing agreements and data sets within 48 hrs.
  • One Click Real Estate 500: The tech dream of instant home purchases: how disruptors will make a monumental financial decision within a necessarily emotional and complex process so easy you don’t even have to think about it. 😉

We’ll dive more into data at Inman Connect New York on Thursday, Jan. 31 at 2 p.mGet tickets here.

Sam DeBord is Managing Broker/VP of Strategic Growth for Coldwell Banker Danforth, Past President of Seattle King County Realtors, and 2019 NAR President’s Liaison for MLS and Data Management. You can find his team at and

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