Many real estate agents are set to gain access to a wide array of multiple listing service (MLS) management tools with the introduction of a new service from Zillow, the listing portal has announced. Retsly Connect, a service powered by listing data aggregator and Zillow subsidiary Retsly, will let software developers create MLS-connected listings management tools that agents can use alongside existing “front end” tools provided by their MLS.

  • Zillow's Retsly Connect offers agents that belong to Retsly MLS partners access to new listing management tools.
  • That's supposed to be a big benefit of AMP, a platform that NAR and Upstream are leveraging to build a listing data collection and distribution platform that's separate from AMP.
  • One difference between AMP, as it's currently planned, and Retsly Connect is that Retsly Connect doesn't support listing entry or editing functionality via various "front ends."

Many real estate agents are set to gain access to a wide array of multiple listing service (MLS) management tools with the introduction of a new service from Zillow, the listing portal has announced.

Retsly Connect, a service powered by listing data aggregator and Zillow subsidiary Retsly, will let software developers create MLS-connected listing management tools that agents can use alongside existing “front end” tools provided by their MLS.

The services will give brokers and agents more choice in what tools they can use to manage and leverage their listings. And it marks a bid by Zillow to counter an industry-led listing aggregation and distribution initiative known as Upstream, some observers say.

Advanced Multi-List Platform (AMP), a platform that Upstream and an NAR subsidiary will leverage to jointly develop a data entry and collection platform, is, “conceptually,” “pretty much identical” to Retsly, said Carlos Grass, the CEO of Stratus Data Systems, which is one of the first two MLS vendors to connect to Retsly Connect.

“This [Retsly Connect] has been a need that the industry has had for years and when we purchased Retsly, they went out and started integrating the data from MLSs,” said Andrea Riggs, director of trade marketing at Zillow Group. “MLSs were saying one problem that you could solve for us is front end choice.”

How Retsly works

Retsly currently collects and standardizes data for software vendors from just six MLSs. It also does the same for public property data, not MLS data, from over 3,000 counties, according to Zillow.

Retsly Connect can pollinate software that makes use of listing data, including search, comparative market analysis (CMA), email, prospecting and market report tools, Riggs said.

Crucially, Retsly Connect will not connect with tools or functionality that let agents or brokers add or edit listings in the MLS, keeping that functionality in the hands of whatever vendor powers an MLS.

First integrations complete

While Retsly has long sought to collect and normalize data from MLSs for the purpose of making it available to tech vendors, Retsly has officially launched Retsly Connect with the rollout of the first two integrations between Retsly and software vendors.

Those vendors are Rapattoni and Stratus Data Systems, both of which provide comprehensive MLS platforms. The integration means agents and brokers who belong to MLSs partnered with Retsly should now be able to use some tools they provide to do a wide array of things with their MLS listings (but not enter or editing them). They are no longer restricted to only using versions of those tools that are provided by the vendor powering their MLS.

In addition to making more listing management tools available to members, MLSs that partner with Retsly, along with their member brokers, receive analytics on how vendors use MLS data, which MLSs and brokers can can consume “for improved market positioning with no additional overhead.”

Stratus screen shot

MLSs maintain control over what vendors and products can access their data through Retsly, and Zillow has said they have “complete transparency” around how their data is used.

A number of industry analysts commented on what they say are clear parallels between Retsly and a collaborative project between Upstream and the National Association of Realtors (NAR). The close resemblances, they say, strongly suggest that Retsly Connet marks a bid by Zillow to preemptively counter the influence that NAR’s and Upstream’s joint initiative may come to wield over the industry.

In partnership with NAR subsidiary RPR, Upstream is building a data entry and collection platform that will function as a middleman between real estate firms and the recipients of their data, which include both MLSs and software vendors.

The project will leverage RPR’s prospective Advanced Multi-List Platform (AMP) to build what RPR CEO Dale Ross has called the “Upstream-AMP system.” While that system would leverage AMP technology, it will be separate from AMP itself, which is a back-end database for small- and medium-sized MLSs.

AMP’s MLS platform is rich with RPR’s property data and is based on the latest industry data standards. As such, it would be able to connect to any standards-based “front end” chosen by brokers. Front ends are the agent-facing part of the MLS, where agents enter and edit their listings and perform comparative market analyses and other functions.

MLSs generally only use the same vendor for both the backend database and the front end application. But AMP would allow brokers and agents to choose to use front ends other than the front end provided by their MLS’s vendor.

That’s what Zillow says Retsly Connect offers agents and brokers: “The option of using the front-end software of their choice.”

It does this in a different manner than AMP, however. Retsly doesn’t power a back-end MLS database that can synchronize with multiple front ends. It serves as a conduit between an MLS’s back end and various front ends, capable of transferring data between the two.

Similar to how AMP can serve as a back-end database for MLSs, the AMP-Upstream system would support a back-end listing database that can connect to multiple front ends, according to a presentation by RPR’s Ross. Brokers supporting Upstream could use the “front end of their choice” to enter, edit and manage listings in the Upstream-AMP listing database.


Asked if Retsly Connect would compete with AMP and Upstream, Riggs only said that Retsly is “certainly an option for brokers and agents.”

But one crucial difference between the AMP-Upstream system (and the AMP MLS product) and Retsly Connect is that AMP would connect with front ends that let agents or brokers enter and edit listing data. Retsly Connect, on the other hand, does not, Riggs said.

Riggs said that “in our mind” listing entry and editing is “something that the MLS owns.”

Another crucial difference between the AMP-Upstream system and Retsly Connect is that Retsly Connect “allows MLSs to keep their business rules in place,” Riggs claimed.

No Upstream representative could immediately be reached for comment, but it’s possible Upstream and NAR would disagree with the implication that the AMP-Upstream system could undermine MLS business rules.

‘Retsly is downstream’

“Retsly is downstream,” Riggs said, clarifying why Retsly must respect MLS rules. “Retsly is dependent on the MLS.”

Through Retsly Connect, Zillow has created “middleware” that enables custom front ends to talk with MLSs, said industry expert Russ Cofano in an email. He initially believed that, for this reason, Retsly Connect was “exactly the concept of the AMP.”

But upon learning that Retsly Connect won’t support listing entry or editing, Cofano concluded that Retsly Connect is really only “somewhat in line with the concept of AMP.”

Cofano said that the difference between Retsly Connect and AMP appears to be that “AMP uses the RPR database as the backend and the ZG offering appears to use the existing MLS (vendor delivered) database and the existing add/edit functionality, thereby keeping the MLS business rules in place.”

“This is a big issue as MLSs tussle with the concept of Upstream and how Upstream will interface with the varying data rules of 700+ MLSs,” he added.

Email Teke Wiggin.

Editor’s note: This story has been updated with comments from Stratus Data Systems CEO Carlos Grass, and to clarify that Retsly collects and normalizes data from six MLSs, and does the same with public data, not MLS data, for 3,000 counties. The six MLSs do not cover 3,000 counties, as a previous version of this story suggested. 

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