CoStar Group Stock (CSGP) Slumps as Google Tests Home Listings in Search: Latest News, Forecasts, and Outlook (Dec. 15, 2025)

CoStar Group, Inc. (NASDAQ: CSGP) took a sharp hit on Monday, December 15, 2025, as investors reacted to reports that Google is testing a new way to display homes-for-sale listings directly inside search results—potentially pressuring the lead-generation economics that power major property portals.

CoStar shares were down roughly 7%–8%, trading around $63 after opening near $68, and touching an intraday low around $62. ^[1] The move put CoStar among the weakest Nasdaq 100 performers on the session, reflecting how sensitive real estate marketplace stocks are to any sign of platform disruption from Alphabet’s search engine. ^[2]

Below is a detailed breakdown of today’s news drivers, the latest analyst forecasts, and the fundamental bull/bear debate shaping CoStar Group stock into year-end.

Why CoStar Group stock dropped today

The immediate catalyst was Google’s reported test of “full home ads” and home listings embedded at the top of mobile search results, with features that resemble what consumers typically get on dedicated portals: property detail pages, the ability to request tours, and options to contact agents. ^[3]

According to coverage replicated by multiple outlets, the test appears limited—showing up for certain users, in certain markets, and primarily on mobile—but even a limited test is enough to spook investors because it raises an uncomfortable question:

If Google keeps the home search journey on Google, what happens to the traffic—and the leads—that flow to portals like Homes.com?

The same Google headlines also knocked peers across the “portal ecosystem,” including Zillow and Rocket, highlighting that the market is treating this as a category-wide threat, not a company-specific misstep. ^[4]

The strategic issue: real estate portals live and die by traffic economics

For real estate marketplaces, the core machine is simple (and brutal):

Get consumer attention (direct traffic, brand, SEO, paid ads)
Convert attention into leads
Monetize leads via agent subscriptions, advertising, or transaction-adjacent services

When Google experiments with keeping users inside search results, investors worry about two second-order effects:

Higher customer acquisition costs: If “free” organic clicks get displaced by Google-controlled placements, portals may have to buy more traffic (or accept slower growth).
Lead dilution: If users request tours/contact agents through a Google layer first, portals risk losing the direct relationship—and the data feedback loop that improves matching, targeting, and conversion over time.

Investopedia noted that analysts see limited immediate impact in part because major portals have built meaningful direct traffic through apps and brand habit—but also warned the risk grows if Google expands the feature. ^[5]

Where Homes.com fits: CoStar’s big bet is still mid-flight

CoStar is not “just” a commercial real estate data company anymore. Over the last two years it has pushed hard to build Homes.com into a scaled consumer marketplace, positioning it as a “portal that works for the listing agent” with its “Your Listing, Your Lead” model.

CoStar’s own disclosures show how central Homes.com has become to the growth narrative:

In Q3 2025, CoStar said the dedicated Homes.com sales team delivered its best net new bookings quarter, and total Homes.com membership surpassed 26,000 members (up nearly 150% vs. the prior year period). ^[6]
Homes.com also reported the “Homes.com Network” reached 115 million average monthly unique visitors in Q3 2025 (as measured by Google Analytics in the company’s disclosure). ^[7]

This is why the Google test matters specifically for CoStar stock: CoStar is spending to build a consumer funnel, and any perceived threat to funnel efficiency tends to hit the multiple fast.

CoStar fundamentals: the latest earnings, bookings, and guidance

While today’s move was headline-driven, CoStar’s underlying fundamentals still anchor the longer-term debate.

Q3 2025 highlights

In its Q3 2025 release, CoStar reported:

Revenue:$834 million, up 20% year-over-year
Net loss:$31 million (GAAP), or -$0.07 per diluted share
Non-GAAP net income:$97 million
Adjusted EBITDA:$115 million, up 51% year-over-year
Net new bookings:$84 million, up 92% year-over-year ^[8]

Management framed the quarter as continued momentum in subscriptions and marketplace demand, while also acknowledging the company is still investing heavily—especially around Homes.com and integration of acquisitions.

Updated 2025 outlook (company guidance)

CoStar also guided:

Full-year 2025 revenue:$3.23B–$3.24B
Q4 2025 revenue:$885M–$895M
Full-year 2025 adjusted EBITDA:$415M–$425M
Q4 2025 adjusted EBITDA:$150M–$160M
Full-year 2025 non-GAAP EPS:$0.82–$0.84
Q4 2025 non-GAAP EPS:$0.26–$0.28 ^[9]

In other words: the business is still growing at a strong clip, but profitability is being managed around an investment cycle that the market alternately rewards (when confidence is high) and punishes (when platform risk spikes).

Analyst forecasts for CoStar Group stock: still “Buy,” but the range is wide

Despite Monday’s selloff, the Street’s broader stance remains constructive—though not unanimous.

Consensus targets (as of Dec. 15, 2025)

A widely-cited compilation of analyst forecasts shows:

Consensus rating:Buy
Average price target: about $94
Low target:$60
High target:$105 ^[10]

That spread is doing a lot of storytelling. It says analysts broadly believe CoStar can recover—yet disagree sharply on how durable Homes.com economics will be and how intense competitive pressures become.

Notable recent calls

Citizens maintained a Market Outperform rating on Dec. 15 and kept a $100 price target (per Investing.com’s report). ^[11]
Needham reiterated a bullish stance earlier in December with a $105 target referenced in public analyst-forecast reporting. ^[12]
On the bearish end, Wells Fargo has been listed with a $60 target and a negative rating in recent consensus tables. ^[13]

A simple way to interpret the dispersion:

Bull case: Homes.com keeps converting spend into durable subscription revenue; commercial products stay resilient; margins recover as growth spend normalizes.
Bear case: Lead-generation gets more expensive (Google, Zillow, shifting traffic mix), forcing sustained marketing intensity and slower margin expansion.

Valuation snapshot: what the market is paying for (and why it’s volatile)

CoStar’s valuation metrics underscore why headlines can swing the stock:

Market cap around $26–27 billion
Extremely high trailing P/E (reflecting low GAAP earnings in the current phase)
Forward P/E and sales multiples that imply the market is still pricing in meaningful future operating leverage ^[14]

This is the classic “growth-with-investment-cycle” setup: the stock behaves less like a slow-and-steady real estate data utility and more like a platform company whose multiple expands or contracts with confidence in its funnel and competitive moat.

Legal and regulatory overhangs: CREXi, Zillow, and IP battles

CoStar also continues to operate with a meaningful litigation backdrop—important because legal outcomes can affect costs, management attention, and competitive strategy.

Supreme Court petition in CREXi antitrust dispute

Reuters reported that CoStar has asked the U.S. Supreme Court to review an antitrust case involving rival CREXi, after an appeals court revived CREXi’s claims. CoStar argues it shouldn’t be forced to provide competitors access to proprietary data/tools and warned the ruling could harm innovation. ^[15]

Zillow copyright litigation

Separately, Reuters reported earlier in 2025 that CoStar (owner of Homes.com) sued Zillow, alleging publication of tens of thousands of copyrighted photos and estimating potential damages could exceed $1 billion. ^[16]

CoStar vs. CREXi: ongoing “copy and crop” dispute

CoStar has also publicly detailed its position in ongoing litigation against CREXi, alleging systematic infringement of CoStar images and content. ^[17]

For investors, these cases function as both:

Moat defense (protecting proprietary content and marketplace integrity), and
Noise and risk (unpredictable timelines, legal expense, and reputational crossfire)

Real estate market context: housing prices up modestly, rents softening

Because CoStar’s platforms sit on top of real estate market activity, macro and property-level data still matter.

Recent CoStar-branded market releases highlighted:

U.S. median home price up 2.4% year-over-year in November to $385,000, with inventory up 17.9% year-over-year (highest November level since 2015, per the report). ^[18]
Apartment rents declining in November, with national average rent at $1,706 and annual rent growth slowing to 0.7%, amid supply pressures in several markets. ^[19]

These trends can cut both ways: more listings and transactions are generally good for marketplaces and data demand, but weak rent growth can intensify competition in rentals—an area where CoStar’s Apartments.com is a major player.

What to watch next for CoStar Group stock

With the stock reacting sharply to platform-risk headlines, the near-term focus for CSGP investors likely shifts to a few concrete signposts:

1) Will Google expand the home-listing test?
Investors will track whether the feature moves beyond limited mobile tests into broader rollout, and whether it becomes a paid channel that portals must participate in to protect lead flow. ^[20]

2) Homes.com monetization metrics
Membership growth, bookings momentum, and evidence that marketing spend is converting into durable, renewing revenue remain the heart of the bull thesis. ^[21]

3) Margin trajectory and 2026 outlook
CoStar’s commercial segment has historically carried strong margins, while newer initiatives create near-term drag. The market will watch for signs that operating leverage is returning without stalling growth. ^[22]

4) Litigation milestones
Any material court developments—especially around the CREXi antitrust dispute—could influence perceptions of CoStar’s competitive conduct and platform strategy. ^[23]

Bottom line

As of December 15, 2025, CoStar Group stock is being pulled between two powerful forces:

A long-term growth story built around scaled real estate marketplaces (especially Homes.com), strong bookings momentum, and expanding product capability, ^[24]
And a platform-risk shock from Google’s latest search experiment—raising fears that the rules of real estate lead generation could shift again, fast. ^[25]

Analysts still skew positive on balance, with consensus targets clustering around the mid-$90s, but the wide target range tells you the market is no longer debating whether CoStar is a major player—it’s debating how expensive dominance will be in an ecosystem where Google can redraw the map with a UI test.