A Big What If on the Eve of RESO Conference

Over on LinkedIn and on Facebook, the real nerds of real estate are posting how they’re en route to South Carolina for the RESO Fall Retreat. Hope my friends have a wonderful time on Kiawah Island.

At the same time, a discussion of sorts has broken out over “native” data dictionary and so on. The post from Sam Debord is here. I’m not all that interested in the intricate details of that particular issue, but the whole back-and-forth got me wondering on the eve of the big RESO get-together.

What if somebody did something real to make RESO unnecessary? What if that somebody were RESO itself, transforming into something… more?

Why Does RESO Exist At All?

On its About Us page, RESO says:

RESO provides the foundation for streamlined real estate technology through the creation and certification of standards. Our member organizations include MLSs, brokerages, REALTOR® associations and technology partners serving more than one million real estate professionals.

I remember when RESO was born, and it was a necessary organization. It still is a necessary organization. But why?

Further down on the About Us page we find:

Open standards organizations, like RESO, exist in most industries to ensure technology advancement. A well-known example is W3C, which creates the standards for the World Wide Web. The most powerful technology companies in the world agree to collaborate to build a common web that raises the technology foundations of all competitors.

This is why you can get data, apps, services, and products from many different competing companies on the same smartphone. Web-based products are built on an open standard.

In real estate, RESO’s standards are created to promote that same experience: interoperability between MLS, broker, agent, and consumer technology tools.

RESO was and remains important because the technology companies in real estate build little silos of proprietary code, proprietary data formats, proprietary features for competitive purposes. But the world needs interoperability. We need to have an app, a piece of software, a data analytics program, whatever work across the country. We’re pretty far from that utopia.

Here’s the thing, though. W3C was founded in 1994; by 2000, it was convincing Netscape to delay launch of its flagship product to become more compliant. There are many reasons why W3C was able to get this kind of influence, including the fact that its founder and managing director is Tim Berners-Lee, the man who could be said to have invented the internet since he developed HTML and HTTP. Some other reasons, perhaps, is that W3C is really operated by large academic institutions: MIT, ERCIM, Keio University and Beihang University. W3C has corporate sponsors, of course, but they’re not dependent on corporate sponsorships or member dues for everything.

In contrast, RESO was founded in 2002 as an NAR Working Group then became an independent organization in 2011. So in 2021, it’s the 10 year anniversary of RESO as an independent organization. And RESO is still cajoling, begging, and asking NAR to enforce things… because it can’t seem to make tech vendors play nice with each other.

Lacking support from major universities and government organizations (the European Union lent substantial support to W3C in its early days), RESO is far more reliant on its corporate sponsors, including NAR, and on membership dues. Some of those corporate sponsors don’t have a ton of interest in playing nice, in interoperability.

This is relevant because the “native” data dictionary thing kind of points to a core issue.

Top Down vs. Bottom Up

The entire native data dictionary thing is hot because NAR has handed down its “Best Practices” guidance:

3. Best Practice: By July 1, 2022, MLSs should create with their vendors and leadership a written plan with a timeline and cost estimate to establish a native* RESO Data Dictionary compliant MLS for all listing content available to MLS Participants and Subscribers.

“Native” means all of the MLS’s data access services for Participants, Subscribers, vendors, designees, and other authorized recipients must be delivered Data Dictionary compliant data without the need to convert it from some other format.

4. Best Practice: Where available, MLSs should share aggregated data, for statistical purposes, with their state association of REALTORS® and NAR to assist with advocacy efforts and home ownership interests.

I post those back to back because it highlights an important part of the puzzle. Both of these “guidances” are top-down from NAR. I’m not aware of a single developer anywhere, or any brokerage or agent anywhere in the country, who was feeling the need to share aggregated data with the state association of REALTORS or NAR to assist with advocacy efforts. If you are one of those, please let me know and I’ll stand corrected.

This is something NAR wants, not something anybody in the technology space or in brokerage space wants.

Maybe #3 on native RESO Data Dictionary compliant MLS is something that tech developers and brokers and agents want, but I wonder. Especially when a prominent member of the tech developer community, Michael Wurzer of FBS, is quoted on Sam’s post questioning the mandate.

So we have “policymakers” who don’t code, who don’t develop software, who don’t build anything at all handing down mandates guidance to those who do. I looked up the members of the MLS Technology and Emerging Issues Advisory Board who passed the native MLS thing, at least of the people whose names I didn’t know immediately. I counted 8 REALTORS, 11 MLS executives, and 2 corporate representatives (Sam DeBord and Jon Coile).

Not one person on that Advisory Board writes code. At least three of the MLSs involved have full-time CTOs, but they weren’t on this Advisory Board.

Contrast that with the people who are involved with W3C. This is the Advisory Board of W3C:

  • Tantek Çelik (Mozilla) – Computer Scientist
  • Heejin Chung (Samsung) – Principle Engineer
  • Tatsuya Igarashi (Sony) – Senior Researcher
  • Florian Rivoal (W3C Invited Expert) – Software Developer
  • Tzviya Siegman (Wiley) – Information Standards Principal
  • David Singer (Apple) – Manager of Software Standards
  • Avneesh Singh (DAISY Consortium) – COO of Daisy (software developer background)
  • Eric Siow (Intel) – Non-technical
  • Léonie Watson (TetraLogical) – engineering background
  • Chris Wilson (Google) – Product Manager
  • Hongru (Judy) Zhu (Alibaba) – Technical Manager

Technologists up and down the list.

Second, W3C doesn’t take orders or even “Best Practices” guidance from anybody outside of itself. And it is evident from the history of W3C that it was a bottom-up organization from the start. Tim Berners-Lee started it, of course, but from the History of the Web:

In 1998, the browser market was dominated by Internet Explorer 4 and Netscape Navigator 4. A beta version of Internet Explorer 5 was then released, and it implemented a new and proprietary dynamic HTML, which meant that professional web developers needed to know five different ways of writing JavaScript.

As a result, a group of professional web developers and designers banded together. This group called themselves the Web Standards Project (WaSP). The idea was that by calling the W3C documents standards rather than recommendations, they might be able to convince Microsoft and Netscape to support them.

W3C from its origins was something that developers and designers and coders wanted, because it made their lives easier. And because it was developers and designers and engineers who came together to make W3C work, the companies had to go along to some extent… because it is those people who actually make the technology they depend on.

At this time, I’m not convinced that RESO is a bottom-up organization that proptech developers and coders want because it makes their lives easier. If it is, then those developers and coders have not broken through to positions of power where they can make a real difference. Look at the RESO Board of Directors if you’d like; I count two people who have coding experience.

So What If…

Imagine if RESO were to transform into a bottom-up organization. What if its Board were not business leaders and policy wonks, but developers, coders, engineers? The men and women who actually have to make something like “native” data dictionary reality. What if it’s the men and women who have to create databases and APIs who were coming together to create standards, instead of a top-down mandate from REALTORS who don’t know Java from Python?

In early 2019, I gave a presentation on the open source future of the MLS at the Clareity conference then recorded a version of it:

In that presentation, I thought RESO would be a big winner from the industry embracing open source software. I still believe that, but I now think that RESO itself needs to embrace the open source philosophy. RESO itself must become bottom-up, rather than top-down. RESO itself must be where coders and developers and engineers come together to work out data standards issues because they need to do that in order to create open source software.

NAR and MLS execs and brokers and agents can and should have input, let the engineers know what needs they have, but otherwise, RESO should follow the lead of W3C and become an organization of technologists, by technologists, for technologists.

The rest of us are their customers, the beneficiaries of their work. They do what they do to make our lives better, easier, and more efficient… but let them figure out how to do that amongst themselves.


All of the vendors who are RESO members, who claim fealty to RESO and its vision, who want interoperability should contribute to an open source MLS software platform. Then keep contributing by letting their software developers work on that open source platform.

Let someone with money to spare, like Zillow or CoreLogic, take the first step. Zillow has Bridge, CoreLogic has Matrix; give it away, guys. Give it away. Let some of the larger brokerages like Compass and Redfin open up the source code of some of their tools. Give it away. Let’s see MLSs that have proprietary code put it into github. Let’s see the various smaller vendors participate, giving away what makes sense and improving what others have put into the pot.

Data standards — even native data dictionary — will arise naturally as actual coders and database developers come together to solve their individual problems for their companies and for their clients.

RESO says web-based products are built on an open standard. That’s true. But they’re also built on open source software that takes advantage of those open standards. Think where the web would be without Linux, Netscape, and hundreds of other open source initiatives.

So. Consider this a call to action for RESO members, particularly those who have actual coders, developers and engineers on payroll and actual software code. Give it away. Donate, step back, and see what the code poets can build for us.


Yes, that bottoms-up, code-centric approach makes RESO unnecessary. We don’t need committee meetings at NAR,  monthly RESO Board meetings and the like, because those are not all that relevant to the code poets building software and agreeing on data standards. The businesspeople need only tell their vendors, their coders, their developers what end result they want to see. Then liberate them to do what they want to do.

The vendors, coders, and developers will need to figure out how to solve their customer’s problems… and given the platform on which to collaborate, they’ll either come together to solve their mutual problems, or they won’t. If they won’t, it’s because it isn’t needed. If they do, it’s because whatever they come up with solves their respective problems.

Open data standards will absolutely be a part of that puzzle, but again, let the engineers responsible for making things happen get together with other engineers to figure out what those ought to be.

If native data dictionary would solve the problems of developers, then they will produce a native data dictionary and make it happen. If it doesn’t, then they won’t. We don’t need bureaucrats and consultants like me conducting studies and such to figure that out. We need database engineers to come together to figure that out.

So RESO in its current form will become unnecessary. But that RESO will be replaced by a far more useful, more influential, and more powerful RESO that can shepherd not only data standards but actual open source software that moves the industry forward. I think RESO should do just that.

Don’t dream big. Give it all away. Don’t have a plan.

And watch the new RESO flourish as it never has before.



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Rob Hahn

Rob Hahn

Managing Partner of 7DS Associates, and the grand poobah of this here blog. Once called "a revolutionary in a really nice suit", people often wonder what I do for a living because I have the temerity to not talk about my clients and my work for clients. Suffice to say that I do strategy work for some of the largest organizations and companies in real estate, as well as some of the smallest startups and agent teams, but usually only on projects that interest me with big implications for reforming this wonderful, crazy, lovable yet frustrating real estate industry of ours.

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