CoStar Group delivered another profitability beat in the third quarter, but the quarter is defined by a widening gap between expanding margins and a weakening top-line engine. Adjusted EPS of $0.38 topped the $0.34 consensus and edged past the $0.37 Earnings Whisper number, a 2.7% surprise, with earnings up 90.0% year over year on the Earnings Whispers basis (the company cites a 65% increase on its own adjusted comparison). Revenue of $952.0 million rose 14.2% and landed essentially in line with the $950.99 million consensus. On a GAAP basis, CoStar earned $0.18 per diluted share versus a $0.07 loss a year ago. The profit story is accelerating. The revenue story is not.

The quality of the beat deserves scrutiny. Adjusted EBITDA doubled to a record $229 million, a 24% margin, and cleared the top of the $190-$210 million guide by $16 million even excluding Zonda. Nearly all of that improvement came from Residential, where adjusted EBITDA swung to $49 million from a $69 million loss a year earlier and $12 million in Q2 as Homes.com spending was pulled back. Commercial adjusted EBITDA was actually slightly lower year over year at $180 million versus $183 million. Selling and marketing fell to $366 million from $418 million and stock-based compensation dropped to $32 million from $71 million, so the earnings leverage reflects cost discipline more than demand. Buybacks also helped: diluted shares fell to roughly 402 million from 420 million, funded by $668 million of repurchases this year, while cash dropped to $500 million from $1.63 billion after $789 million of acquisition spending.

The top line tells a different story. Year-over-year revenue growth has slowed from about 22% in Q1 to 18% in Q2 to 14% now, and the Q4 guide implies roughly 10%, with acquisitions doing much of the work. Excluding Zonda, Q3 revenue of $933 million was about $7 million below the guidance midpoint. Net new bookings collapsed to $37 million from $69 million in Q2 and $84 million a year ago, which management attributed to macro conditions and a sales force about 10% smaller. Apartments.com growth slowed to 6% from 9% in Q2, paid properties fell 2% sequentially, and Q4 is guided to mid-single digits. Homes.com growth decelerated to 50% from 66%, with membership flat around 36,000 after inside sales reps were cut to 267 from 655. Domain fell 5% pro forma amid Australian housing weakness. Management's tone has moved from Q1's confident framing to a candid admission of recruiting and execution shortfalls, an HR overhaul, and a pivot toward field sales, while describing Q3 as the bookings trough.

Guidance splits along the same line. Full-year adjusted EBITDA guidance rose to $820-$840 million, the third increase this year, and adjusted EPS guidance moved to $1.38-$1.41. Reported revenue guidance edged up to $3.75-$3.77 billion only because of Zonda. Excluding the acquisition, the full-year revenue outlook fell about $35 million, the second consecutive organic cut, and Commercial guidance was trimmed to $1.935-$1.945 billion. Revenue guidance came in below expectations. On the catalyst side, management identified at least $200 million of additional savings over 12 to 18 months, on top of $150 million of 2026 savings versus the original plan, and reaffirmed its $1.25 billion 2028 adjusted EBITDA target. The roughly $730 million Vexcel deal, about $140 million of revenue growing 30%-plus and expected to be accretive in year one, sits outside guidance. Early Homes.com Platinum pricing, with October average sale price up 58% to $429, and a 30% sequential jump in LoopNet bookings are encouraging but small against the broader bookings decline.

Investors came in braced for a difficult setup. Earnings Whispers sentiment remained negative but improved to -0.24 from -0.32 ahead of the report. The stock has rallied 29.5% since the open after the July report, rebounding from a 52-week low of $25.89 set on July 29. Shares entered the print at $33.70, about 5% below the October 22 quarterly high but still nearly 10% beneath the 200-day moving average. The Earnings Whispers trend readings lean positive, with sequential growth and AVWAP favorable while price and momentum are neutral. That rebound suggests a good portion of the margin story was already being rewarded before this release.

The bottom line is that CoStar is delivering on its promise to harvest profits, and the cost program gives the $1.25 billion 2028 target credible support. But bears have legitimate ammunition: bookings have nearly halved sequentially, organic revenue guidance has been cut twice, and core marketplaces are decelerating while the company shrinks its sales force and leans on acquisitions. Until bookings demonstrably bottom as management claims, the earnings beats will be read as cost-driven rather than evidence of renewed demand.