CoStar Group, Inc.
US ˙ NasdaqGS ˙ US22160N1090

SecurityCSGP / CoStar Group, Inc.
InstitutionAxa S.a.
Latest Disclosed Ownership13,908 shares
Latest Disclosed Value $ 561,049
Axa S.a. reports 28.63% increase in ownership of CSGP / CoStar Group, Inc.

On May 15, 2026 - Axa S.a. filed a 13F-HR form disclosing ownership of 13,908 shares of CoStar Group, Inc. (US:CSGP) valued at $561,049 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 10,812 shares of CoStar Group, Inc.. This represents a change in shares of 28.63% during the quarter. The current value of the position is $464,527 USD.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

Upgrade to unlock premium data and export to Excel .

Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date
Effective
Date
Form Security Class ID Avg Price
Paid (Est)
Reported
Shares
ΔShares ΔShares
(%)
Reported
Value
(x1000)
ΔValue
(%)
Alloc
(%)
ΔAlloc ΔAlloc (%) Cost Basis
(x1000)
Unrealized
Gain/Loss
(x1000)
2026-05-15 2026-03-31 13F COSTAR GROUP COM 22160N109 13,908 3,096 28.63 561 -22.73 0.1978
2026-02-13 2025-12-31 13F COSTAR GROUP COM 22160N109 10,812 10,812 727 0.3440
2025-11-14 2025-09-30 13F COSTAR GROUP COM 22160N109 0 -39,822 -100.00 0 -100.00
2025-08-14 2025-06-30 13F COSTAR GROUP COM 22160N109 39,822 5,749 16.87 3,202 18.60 0.0092
2025-05-15 2025-03-31 13F COSTAR GROUP COM 22160N109 34,073 2,179 6.83 2,700 18.22 0.0089
2025-02-14 2024-12-31 13F COSTAR GROUP COM 22160N109 31,894 -3,233 -9.20 2,283 -13.82 0.0069
2024-11-14 2024-09-30 13F COSTAR GROUP COM 22160N109 35,127 4,338 14.09 2,650 16.08 0.0078
2025-02-25 2024-06-30 13F/A-1 COSTAR GROUP COM 22160N109 30,789 120 0.39 2,283 -22.96 0.0068
2024-08-14 2024-06-30 13F COSTAR GROUP COM 22160N109 30,789 120 2,283 0.0068
2024-05-15 2024-03-31 13F COSTAR GROUP COM 22160N109 30,669 4,264 16.15 2,963 28.39 0.0089
2024-07-16 2023-12-31 13F/A-1 COSTAR GROUP COM 22160N109 26,405 3,405 14.80 2,308 30.49 0.0074
2024-02-14 2023-12-31 13F COSTAR GROUP COM 22160N109 26,405 3,405 2,308 0.0045
2023-11-14 2023-09-30 13F COSTAR GROUP COM 22160N109 23,000 -154 -0.67 1,768 -14.17 0.0062
2023-08-14 2023-06-30 13F COSTAR GROUP COM 22160N109 23,154 -1,484 -6.02 2,061 21.46 0.0068
2023-05-15 2023-03-31 13F COSTAR GROUP COM 22160N109 24,638 -168,213 -87.22 1,696 -88.62 0.0058
2023-02-14 2022-12-31 13F COSTAR GROUP COM 22160N109 192,851 170,086 747.14 14,904 840.25 0.0538
2023-02-14 2022-09-30 13F/A-1 CoStar Group COM 22160N109 22,765 18,317 411.80 1,586 491.42 0.0062
2022-11-14 2022-09-30 13F CoStar Group COM 22160N109 22,765 18,317 1,585 0.0062
2023-02-14 2022-06-30 13F/A-1 CoStar Group COM 22160N109 4,448 179 4.19 269 -5.63 0.0010
2022-08-15 2022-06-30 13F CoStar Group COM 22160N109 4,448 179 268 0.0010
2023-02-14 2022-03-31 13F/A-1 CoStar Group COM 22160N109 4,269 -23,906 -84.85 284 -87.25 0.0008
2022-05-13 2022-03-31 13F CoStar Group COM 22160N109 4,269 -23,906 284 0.0008
2022-02-14 2021-12-31 13F CoStar Group COM 22160N109 28,175 -1,466 -4.95 2,227 -12.70 0.0057
2021-11-15 2021-09-30 13F CoStar Group COM 22160N109 29,641 -4,999 -14.43 2,551 -11.08 0.0072
2021-08-13 2021-06-30 13F/A-1 CoStar Group COM 22160N109 34,640 30,820 806.81 2,869 -8.63 0.0081
2021-08-13 2021-06-30 13F CoStar Group COM 22160N109 34,640 30,820 2,869 0.0048
2021-05-14 2021-03-31 13F CoStar Group COM 22160N109 3,820 -4,144 -52.03 3,140 -57.34 0.0096
2021-02-12 2020-12-31 13F CoStar Group COM 22160N109 7,964 -2,246 -22.00 7,361 -15.03 0.0231
2021-02-11 2020-09-30 13F/A-1 CoStar Group COM 22160N109 10,210 -279 -2.66 8,663 16.24 0.0313
2020-11-13 2020-09-30 13F CoStar Group COM 22160N109 10,210 -279 8,663 17,292.7229
2021-02-12 2020-06-30 13F/A-1 COSTAR GROUP COM 22160N109 10,489 -7,852 -42.81 7,453 -30.79 0.0294
2020-08-14 2020-06-30 13F COSTAR GROUP COM 22160N109 10,489 -7,852 7,453 29,391.9931
2021-02-12 2020-03-31 13F/A-2 COSTAR GROUP COM 22160N109 18,341 -6,401 -25.87 10,769 -27.26 0.0538
2020-06-15 2020-03-31 13F/A-1 COSTAR GROUP COM 22160N109 18,341 0 10,769 0.0539
2020-05-15 2020-03-31 13F COSTAR GROUP COM 22160N109 18,341 -6,401 10,769 29,948.7742
2021-02-12 2019-12-31 13F/A-1 COSTAR GROUP COM 22160N109 24,742 -22,169 -47.26 14,804 -46.80 0.0602
2020-02-18 2019-12-31 13F COSTAR GROUP COM 22160N109 24,742 -22,169 14,804 60,276.8263
2021-02-12 2019-09-30 13F/A-1 COSTAR GROUP COM 22160N109 46,911 36,599 354.92 27,827 387.00 0.1107
2019-11-14 2019-09-30 13F COSTAR GROUP COM 22160N109 46,911 36,599 27,827 110,892.3665
2021-02-12 2019-06-30 13F/A-1 COSTAR GROUP COM 22160N109 10,312 866 9.17 5,714 29.69 0.0223
2019-08-13 2019-06-30 13F COSTAR GROUP COM 22160N109 10,312 866 5,714 22,407.9046
2019-05-14 2019-03-31 13F COSTAR GROUP COM 22160N109 9,446 3,691 64.14 4,406 127.00 0.0172
2019-02-13 2018-12-31 13F COSTAR GROUP COM 22160N109 5,755 5,755 1,941 0.0085
2018-11-08 2018-09-30 13F COSTAR GROUP COM 22160N109 0 -6,055 -100.00 0 -100.00
2018-08-13 2018-06-30 13F COSTAR GROUP COM 22160N109 6,055 5,267 668.40 2,499 773.78 0.0096
2018-05-14 2018-03-31 13F COSTAR GROUP COM 22160N109 788 788 286 0.0011
2017-02-13 2016-12-31 13F COSTAR GROUP COM 22160N109 0 -37,600 -100.00 0 -100.00
2016-11-10 2016-09-30 13F COSTAR GROUP COM 22160N109 37,600 -3,647 -8.84 8,142 -9.72 0.0358
2016-08-11 2016-06-30 13F COSTAR GROUP COM 22160N109 41,247 -195 -0.47 9,019 15.66 0.0402
2016-05-13 2016-03-31 13F COSTAR GROUP COM 22160N109 41,442 -200 -0.48 7,798 -9.40 0.0350
2016-02-12 2015-12-31 13F COSTAR GROUP COM 22160N109 41,642 686 1.67 8,607 21.43 0.0376
2015-11-13 2015-09-30 13F COSTAR GROUP COM 22160N109 40,956 -13,200 -24.37 7,088 -34.97 0.0291
2015-08-13 2015-06-30 13F COSTAR GROUP COM 22160N109 54,156 -853 -1.55 10,899 0.16 0.0436
2015-05-13 2015-03-31 13F COSTAR GROUP COM 22160N109 55,009 -17,611 -24.25 10,882 -18.40 0.0448
2015-02-13 2014-12-31 13F COSTAR GROUP COM 22160N109 72,620 1,400 1.97 13,335 20.37 0.0535
2014-11-13 2014-09-30 13F COSTAR GROUP COM 22160N109 71,220 1,300 1.86 11,078 0.17 0.0474
2014-08-13 2014-06-30 13F COSTAR GROUP COM 22160N109 69,920 33,200 90.41 11,059 61.28 0.0460
2014-05-13 2014-03-31 13F COSTAR GROUP COM 22160N109 36,720 35,000 2,034.88 6,857 2,063.09 0.0298
2014-02-13 2013-12-31 13F COSTAR GROUP COM 22160N109 1,720 0 0.00 317 9.69 0.0014
2013-11-13 2013-09-30 13F COSTAR GROUP COM 22160N109 1,720 -138 -7.43 289 20.42 0.0014
2013-08-12 2013-06-30 13F COSTAR GROUP COM 22160N109 1,858 1,858 240 0.0013
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.