When the National Association of Realtors’ board of directors meets next month, the group will vote on whether to repeal a controversial rule on sharing listings data with non-MLS members.

But that may not be enough to put a lid on a simmering controversy which boiled over at the groups’ mid-year meeting in May, as brokers around the country confront the issue of who and how to allow access to listings data.

As the data wars heat up, it’s multiple listing services across the country who may find themselves in the cannibal’s pot.

“I wouldn’t say people are discontented with the MLS,” said Kathy Condon, CEO of MLS PIN, Massachusetts’ biggest multiple listing service. “But the MLSs are spending a big amount of their time trying to keep themselves relevant in this economy, with all the new technology.”

Nuclear Option

The controversial “franchise IDX” rule was strenuously opposed by two coalitions of independent brokers, who feared it would give a huge leg up to local franchise offices of national brands like Coldwell Banker and RE/MAX.

But the reason the big national brands pushed for the rule in the first place was their fear of being outgunned by third-party websites like Zillow and Trulia, which already offer nationwide real estate listings. According to recent weekly stats from Experian Hitwise, an Internet traffic analysis firm, earlier this month Zillow shot to the number 1 slot as the most-visited real estate website in the country.

Trends like that could inspire some national firms to find a loophole in NAR’s rules, according to Rob Hahn, founder and managing partner of Texas-based real estate and business consulting firm 7DS Assoc.

“If the franchisors really believe that competing with [sites like Zillow and Trulia] is critical to their survival,” Hahn wrote recently on his blog, they could simply create a search engine of their own to crawl listings, the way Google does. Search engines are specifically exempt from the IDX ban under the rule.

Such a move might be the real estate version of the nuclear option, and no firm has suggested it’s something they seriously plan to undertake. But that Hanh – a former marketing director for Realogy – would find such a move even thinkable suggests how intense the competition over real estate data is getting.

“I wouldn’t put it past them,” he told Banker and Tradesman. “There’s so much political uncertainty around this issue.”

The fear is that brokerages could end up “outsourc[ing] our brains” to third-party sites, as Redfin CEO Glen Kelman put it in a conference call with real estate agents hosted by agent blog portal Active Rain. If consumers come to rely on third parties to find data on home sales, “they are going to make all of the money, and we are going to do all of the work,” said Kelman.

Of course, Kelman was only on the call in order to help calm the trouble stirred up by his site’s “Scouting Report,” which used MLS data to compile stat sheets on individual Realtors. The Scouting Report was quickly pulled after agents objected to inaccuracies in the data presented.

But as companies like Redfin push the envelope on what can and can’t be done with MLS data, and agents clamor for ways to put listings on sites like Twitter and Facebook, many brokers are growing more leery of allowing their listings to be put on other people’s websites at all.

And multiple listing services are caught in the middle.

‘Do No Harm’

One possible solution is for MLSs to develop public-facing websites, which would ensure consumers were getting the most accurate listings data, in a place operated for the benefit of member brokerages. In Massachusetts, the Berkshire County Board of Realtors operates is own MLS, which has a public search feature. Condon said she and her board were definitely considering the possibility.

Setting up a public MLS is “probably a discussion MLS PIN is going to have within the next 12 months,” Condon said. “We were one of the first MLSs in the country back in 1999 and 2000 that had one. And we were asked to take it down by our broker owners and we did so. With the data being so out there now, you wonder, would they think differently?”

But having a public-facing MLS site can cause friction itself, warns Brian Larson, a Minnesota-based lawyer and consultant who helped pioneer Internet listing sharing.

“In a way, it doesn’t matter [whether you promote your site or not], if your site ends up getting a lot of traffic, what brokers are going to say is, ‘The MLS site got 30,000 visitors last month. Where would those visitors have gone if they didn’t go to the MLS site?’” he explained.

Nevertheless, in view of the changing real estate data landscape, he said he thinks a public MLS site can be beneficial.

“My default position before was, ‘The MLS should do no harm, and if the brokers believe it would hurt them to do this, the MLS should stay out of it.’ My view now is, ‘That’s the sort of strategic abdication,’” which has opened the door to third party sites like Zillow. “It makes more sense to say the MLS should proceed to [create a public site] unless the brokers show that’s it going to cause harm, unless they’ve got data from somewhere.”

“The important thing that MLSs have to remember is to get those leads back to their brokers,” Condon said. “And most MLSs are doing that.”