More than 1,500 people listing properties on the site have multiple listings, with 180 listing five or more properties or rooms across London.
policy adviser, said: "We're disappointed with the way these lists work, and feel consumers who install multiple lists could be left with a false sense of security".
There are also different views, including: a sidebar for day-to-day use, an expanded view with multiple lists for discussions and priorities and a full-screen mode.
Twitter does this on a rolling basis with multiple lists on its Year in Review page, which includes notable people who joined Twitter in 2011 (Charlie Sheen, Sean Parker, and Howard Stern) and its just-added lists of hot topics.
Resales of homes costing more than $1 million have slowed in the past year, according to multiple listing figures, with houses lingering longer on the market and sales prices dipping a bit from asking prices.
It also recently acquired Retsly, a service that helps developers access real estate listing and it has worked out deals with multiple listing services to get direct access to their real estate listings.
In this role, the company says, he will be responsible for building and strengthening Zillow's relationships with multiple listing services (MLSs) and other industry partners.
He says the company believes it is using the agent data in compliance with its licensing agreements with the multiple listing services, where agents list properties for sale.
For example, he said, with most multiple listing services, the system administrator maintains data on previous listings and completed sales that participating brokers can use in marketing new properties.
The research found that listing a house with a multiple listing service in Madison did indeed shorten the time it took to sell the property.
