Core Viewpoint - Shares of online real estate listing companies fell sharply due to Google's testing of a new ad format that displays homes-for-sale listings directly in search results, posing a threat to property portals' traffic and leads [1][3]. Group 1: Market Reaction - Zillow Group experienced a significant decline, with shares down 10.8%, marking its steepest fall since March 2024 and the lowest close since late May 2025 [1]. - Other real estate platforms also faced sharp sell-offs, with CoStar Group down about 7.8% and Rocket Companies down 4.7%, both heading for their lowest closes in years [2]. Group 2: Google’s New Feature - Google is testing a feature that displays home listings directly in search results, which could disrupt the traditional model of directing users to third-party portals [3]. - The feature includes property detail pages, options to request tours, and links to contact agents, which are central to the business model of real estate portals [4]. Group 3: Functionality of the Feature - The new ad format shows a carousel of property photos, prices, and details such as bedrooms and square footage at the top of search results for specific queries [5]. - Clicking on a listing leads to a detailed page with options to request a tour or contact a local agent, who typically responds within a few hours [6]. Group 4: Analyst Perspectives - Analysts view the test as a negative development for Zillow, as it could impact its Premier Agent program, which connects homebuyers with agents [8]. - Despite the potential long-term risks from Google's move, analysts like Robert Mollins maintain a buy rating on Zillow, suggesting that the test is unlikely to affect its market share or revenue growth in the near term [9]. - Goldman Sachs also maintains a Neutral rating on Zillow, emphasizing that most of its traffic comes from its own websites and apps rather than Google search [10].