| Filer | Ownership | Change % | Holdings Value | Net Change | Nb Shares | Change % | Reporting Name | Report Period |
|---|---|---|---|---|---|---|---|---|
| BlackRock, Inc. | 7.5% | $2,631,535,419 | 31,820,259 | BlackRock, Inc. | 31 Mar 2025 |
As of 31 Dec 2025, 831 institutional investors reported holding 411,594,819 shares of COSTAR GROUP, INC. - Common Stock (CSGP). This represents 97% of the company’s total 424,270,120 outstanding shares.
The largest institutional shareholders of COSTAR GROUP, INC. - Common Stock (CSGP) together control 66% of the company’s outstanding shares — a level of ownership often associated with strong institutional conviction and long‑term capital commitment.
| Institution | Ownership % | Shares Held | Share Change % | Portfolio % | Holdings Value |
|---|---|---|---|---|---|
| VANGUARD GROUP INC | 17% | 70,108,999 | +0.08% | 0.07% | $4,714,129,093 |
| BlackRock, Inc. | 8% | 33,970,626 | -6% | 0.04% | $2,284,184,864 |
| BAMCO INC /NY/ | 4.6% | 19,498,099 | +1.3% | 3.6% | $1,311,052,177 |
| STATE STREET CORP | 4.4% | 18,632,352 | +1.9% | 0.04% | $1,252,839,348 |
| PRINCIPAL FINANCIAL GROUP INC | 4.1% | 17,566,074 | -5.7% | 0.6% | $1,181,146,072 |
| BAILLIE GIFFORD & CO | 3% | 12,933,185 | +57% | 0.72% | $869,627,359 |
| GEODE CAPITAL MANAGEMENT, LLC | 2.9% | 12,182,167 | -3.3% | 0.05% | $816,237,290 |
| Capital International Investors | 2.6% | 10,842,010 | +60% | 0.11% | $729,019,965 |
| AKRE CAPITAL MANAGEMENT LLC | 2.3% | 9,617,805 | +3.3% | 7.1% | $646,701,208 |
| JANUS HENDERSON GROUP PLC | 1.8% | 7,473,380 | +20% | 0.23% | $502,487,485 |
| NORGES BANK | 1.7% | 7,090,495 | 0.05% | $476,764,884 | |
| Capital Research Global Investors | 1.3% | 5,566,962 | +11% | 0.07% | $374,328,936 |
| Invesco Ltd. | 1.3% | 5,387,056 | +19% | 0.06% | $362,225,646 |
| MORGAN STANLEY | 1.2% | 5,291,136 | -38% | 0.02% | $355,776,152 |
| POLEN CAPITAL MANAGEMENT LLC | 1.2% | 4,890,936 | -23% | 1.4% | $328,866,546 |
| Vulcan Value Partners, LLC | 1.1% | 4,485,021 | +17% | 5.5% | $301,527,000 |
| MIZUHO MARKETS AMERICAS LLC | 1% | 4,416,116 | -14% | 6.4% | $296,939,640 |
| Amundi | 0.97% | 4,114,516 | +31% | 0.09% | $276,660,055 |
| Bank of New York Mellon Corp | 0.97% | 4,113,002 | -5.7% | 0.05% | $276,558,187 |
| NOMURA ASSET MANAGEMENT INTERNATIONAL INC. | 0.92% | 3,909,161 | 0% | 0.4% | $262,852,000 |
| GOLDMAN SACHS GROUP INC | 0.88% | 3,751,312 | +71% | 0.04% | $252,238,230 |
| Nuveen, LLC | 0.84% | 3,560,896 | +1.5% | 0.06% | $239,434,647 |
| BANK OF AMERICA CORP /DE/ | 0.83% | 3,504,812 | -5.2% | 0.02% | $235,663,552 |
| NORTHERN TRUST CORP | 0.82% | 3,466,062 | -7.6% | 0.03% | $233,058,008 |
| T. Rowe Price Investment Management, Inc. | 0.82% | 3,464,794 | -1.3% | 0.15% | $232,973,000 |
| Period | Reported Shares, Excl. Options | Value, Excl. Options | Value Change | Price (Median) | Investors |
|---|---|---|---|---|---|
| 2025 Q4 | 411,594,819 | $27,663,616,329 | -$292,944,049 | $67.24 | 831 |
| 2025 Q3 | 413,426,235 | $34,855,153,600 | -$902,869,837 | $84.37 | 894 |
| 2025 Q2 | 424,703,791 | $34,159,019,628 | +$171,132,190 | $80.40 | 862 |
| 2025 Q1 | 423,446,348 | $33,523,790,279 | +$1,607,628,234 | $79.23 | 849 |
| 2024 Q4 | 403,038,641 | $28,852,435,346 | +$370,626,438 | $71.59 | 792 |
| 2024 Q3 | 397,246,146 | $29,969,181,073 | +$120,726,429 | $75.44 | 760 |
| 2024 Q2 | 394,901,262 | $29,273,363,324 | -$291,836,744 | $74.14 | 748 |
| 2024 Q1 | 396,743,013 | $38,303,855,847 | +$428,598,484 | $96.60 | 755 |
| 2023 Q4 | 393,483,055 | $34,375,409,230 | +$143,130,803 | $87.39 | 730 |
| 2023 Q3 | 391,788,209 | $30,120,902,945 | -$590,586,683 | $76.89 | 680 |
| 2023 Q2 | 397,474,758 | $35,363,122,789 | +$989,211,981 | $89.00 | 704 |
| 2023 Q1 | 388,559,886 | $26,741,702,121 | -$376,407,464 | $68.85 | 681 |
| 2022 Q4 | 392,580,944 | $30,340,252,937 | -$724,471,352 | $77.28 | 694 |
| 2022 Q3 | 401,886,577 | $27,995,359,544 | +$1,018,881,581 | $69.65 | 619 |
| 2022 Q2 | 380,103,098 | $22,960,291,091 | +$139,282,945 | $60.41 | 570 |
| 2022 Q1 | 378,297,654 | $25,170,499,125 | +$109,334,737 | $66.61 | 571 |
| 2021 Q4 | 374,835,876 | $29,611,659,956 | -$73,412,177 | $79.03 | 614 |
| 2021 Q3 | 375,161,636 | $32,269,957,641 | -$34,760,974 | $86.06 | 587 |
| 2021 Q2 | 375,105,287 | $31,053,499,414 | +$27,703,708,016 | $82.82 | 594 |
| 2021 Q1 | 37,937,694 | $31,162,910,100 | +$177,339,216 | $821.89 | 577 |
| 2020 Q4 | 37,666,252 | $34,793,341,330 | -$174,310,813 | $924.28 | 609 |
| 2020 Q3 | 37,840,096 | $32,096,827,188 | +$152,748,862 | $848.51 | 569 |
| 2020 Q2 | 37,755,916 | $26,814,722,649 | +$1,880,573,285 | $710.67 | 531 |
| 2020 Q1 | 35,124,109 | $20,625,948,296 | +$78,017,926 | $587.21 | 493 |
| 2019 Q4 | 34,887,669 | $20,871,701,673 | +$162,572,354 | $598.30 | 483 |
| 2019 Q3 | 34,625,145 | $20,534,437,608 | -$309,418,698 | $593.20 | 478 |
| 2019 Q2 | 35,092,487 | $19,429,213,866 | +$95,073,440 | $554.06 | 439 |
| 2019 Q1 | 35,440,815 | $16,526,927,390 | +$92,404,619 | $466.42 | 430 |
| 2018 Q4 | 35,247,092 | $11,887,308,822 | +$13,188,600 | $337.34 | 377 |
| 2018 Q3 | 35,145,115 | $14,789,748,496 | -$83,958,817 | $420.84 | 402 |
| 2018 Q2 | 35,347,408 | $14,585,049,143 | -$78,222,302 | $412.63 | 376 |
| 2018 Q1 | 35,556,148 | $12,894,936,556 | +$38,902,943 | $362.68 | 355 |
| 2017 Q4 | 35,553,087 | $10,556,304,923 | -$150,769,950 | $296.95 | 337 |
| 2017 Q3 | 36,114,148 | $9,686,049,694 | +$936,329,738 | $268.25 | 333 |
| 2017 Q2 | 32,609,721 | $8,595,866,765 | +$543,170,527 | $263.60 | 296 |
| 2017 Q1 | 32,990,544 | $6,835,782,488 | +$240,918,276 | $207.22 | 283 |
| 2016 Q4 | 33,323,463 | $6,282,123,160 | +$58,008,591 | $188.49 | 288 |
| 2016 Q3 | 33,085,002 | $7,161,342,232 | -$149,516,946 | $216.53 | 238 |
| 2016 Q2 | 33,670,668 | $7,362,191,776 | -$101,209,888 | $218.66 | 247 |
| 2016 Q1 | 34,237,430 | $6,439,519,077 | +$89,330,867 | $188.17 | 225 |
| 2015 Q4 | 33,774,059 | $6,981,086,116 | +$4,799,371 | $206.69 | 217 |
| 2015 Q3 | 33,842,907 | $5,856,788,480 | -$34,726,181 | $173.06 | 221 |
| 2015 Q2 | 33,108,869 | $6,663,510,644 | -$168,762,739 | $201.26 | 214 |
| 2015 Q1 | 33,782,554 | $6,682,194,023 | +$72,190,149 | $197.83 | 212 |
| 2014 Q4 | 33,703,923 | $6,189,337,643 | +$73,294,135 | $183.63 | 210 |
| 2014 Q3 | 33,225,437 | $5,168,157,522 | +$207,752,740 | $155.54 | 205 |
| 2014 Q2 | 31,913,694 | $5,045,424,648 | +$611,554,696 | $158.17 | 233 |
| 2014 Q1 | 27,940,865 | $5,214,663,264 | +$113,713,900 | $186.74 | 234 |