New York, May 17, 2026, 15:01 (EDT)
- CoStar ended Friday at $32.68, up 2.6%. Trading volume jumped with a Nasdaq-100 exit on the horizon.
- Nasdaq said Lumentum will take CoStar’s spot in the index ahead of Monday’s open.
- Index-fund flows, how Homes.com performs, and CoStar’s look at retail markets at ICSC Las Vegas are likely to be in focus this week.
CoStar Group is set to drop out of the Nasdaq-100 before Monday’s open. The real estate data and marketplace firm closed out Friday on firmer ground, but its index fate is less steady.
The Nasdaq-100 is more than a name now. Nasdaq says the index tracks 100 of the biggest Nasdaq-listed non-financial firms, and over 200 products with more than $600 billion linked to it. Funds that follow the index could change their positions if a stock gets dropped. Lumentum Holdings will step in for CoStar, according to Nasdaq.
U.S. markets stayed closed on Sunday. The next trading session for the NYSE and Nasdaq is set for Monday. Trading runs weekdays from 9:30 a.m. to 4 p.m.
CoStar shares jumped 2.6% to $32.68 on Friday, up from $31.85 Thursday, based on LSEG data. Trading was heavy, with 37.8 million shares changing hands, over four times this week’s average through Thursday.
CoStar’s late rebound on Friday wasn’t enough to erase earlier losses for the week. Shares finished at $32.92 Monday, $33.05 Tuesday, $31.97 Wednesday, and $31.85 Thursday. The last-session move lifted the stock but didn’t change the week’s direction.
CoStar ended Friday ahead as the S&P 500 dropped 1.24% and the Dow shed 1.07%, MarketWatch said. The report noted CoStar is still well under its 52-week high of $97.43.
CoStar’s first quarter numbers are more mixed. The company posted revenue of $897 million, up 23% year over year, with adjusted EBITDA at $132 million. Adjusted EBITDA—earnings before interest, taxes, depreciation and amortization, minus some items—is a metric investors often track as a proxy for profit.
CoStar CEO Andy Florance said there is “strong momentum” in Homes.com members, as CFO Christian Lown pointed to “strong revenue and Adjusted EBITDA growth.” The company kept its 2026 revenue target at $3.78 billion to $3.82 billion and raised its full-year adjusted EBITDA forecast to a range of $780 million to $820 million. Business Wire
Homes.com keeps weighing on the stock. CoStar’s quarterly filing showed Residential Real Estate revenue up 32% to $425 million in the first quarter. Still, the segment ended with an adjusted EBITDA loss of $29 million. Commercial Real Estate adjusted EBITDA came in at $161 million.
CoStar’s push into residential is drawing attention as it lines up against Zillow, the top U.S. online real estate portal, and other listing sites. Reuters last year called CoStar the owner of Homes.com and Apartments.com when it covered CoStar’s lawsuit against Zillow over real estate photos.
CoStar heads into the week with a chance to highlight its main data unit. In a May 15 retail market note, the firm said U.S. retail availability was still about 15% under its last 10-year average. Brandon Svec, national director of retail analytics, said “new supply remains very thin.” Svec will present Tuesday at ICSC Las Vegas. CoStar Group
Friday saw heavy trading in a rebound that may have been more about index positioning than sentiment on the company itself. If passive outflows hit at the open on Monday, or if investors think Homes.com will eat up more time and cash than CoStar’s guidance suggested, shares might have trouble, even with better commercial property numbers in the background.
