CoStar Group, Inc.
MX ˙ BMV ˙ US22160N1090
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityMX:CSGP / CoStar Group, Inc.
InstitutionNorthwestern Mutual Wealth Management Co
Latest Disclosed Ownership16,221 shares
Latest Disclosed Value $ 654,355
Northwestern Mutual Wealth Management Co reports 59.31% decrease in ownership of CSGP / CoStar Group, Inc.

On May 7, 2026 - Northwestern Mutual Wealth Management Co filed a 13F-HR form disclosing ownership of 16,221 shares of CoStar Group, Inc. (MX:CSGP) valued at $654,355 USD as of March 31, 2026. The entity filed a previous 13F-HR/A on February 10, 2026 disclosing 39,867 shares of CoStar Group, Inc.. This represents a change in shares of -59.31% during the quarter.

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.

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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)
2026-05-07 2026-03-31 13F COSTAR GROUP COM 22160N109 16,221 -23,646 -59.31 654 -75.60 0.0004
2026-02-10 2025-12-31 13F/A-1 COSTAR GROUP COM 22160N109 39,867 -15,367 -27.82 2,681 -42.49 0.0017
2026-02-05 2025-12-31 13F COSTAR GROUP COM 22160N109 68,766 13,532 1,949 0.0012
2025-11-14 2025-09-30 13F COSTAR GROUP COM 22160N109 55,234 -34,258 -38.28 4,660 -35.23 0.0031
2025-08-13 2025-06-30 13F COSTAR GROUP COM 22160N109 89,492 -64 -0.07 7,195 1.41 0.0052
2025-05-14 2025-03-31 13F COSTAR GROUP COM 22160N109 89,556 -119,505 -57.16 7,095 -52.59 0.0058
2025-02-11 2024-12-31 13F COSTAR GROUP COM 22160N109 209,061 17,488 9.13 14,967 3.56 0.0126
2024-11-12 2024-09-30 13F COSTAR GROUP COM 22160N109 191,573 26,507 16.06 14,452 18.10 0.0128
2024-08-16 2024-06-30 13F COSTAR GROUP COM 22160N109 165,066 16,084 10.80 12,238 -14.97 0.0121
2024-05-15 2024-03-31 13F COSTAR GROUP COM 22160N109 148,982 -2,009 -1.33 14,392 9.06 0.0148
2024-02-13 2023-12-31 13F COSTAR GROUP COM 22160N109 150,991 9,829 6.96 13,195 21.58 0.0149
2023-11-14 2023-09-30 13F COSTAR GROUP COM 22160N109 141,162 3,000 2.17 10,854 -11.74 0.0141
2023-08-14 2023-06-30 13F COSTAR GROUP COM 22160N109 138,162 3,579 2.66 12,296 32.70 0.0159
2023-05-15 2023-03-31 13F COSTAR GROUP COM 22160N109 134,583 9,157 7.30 9,266 -4.40 0.0129
2023-02-21 2022-12-31 13F COSTAR GROUP COM 22160N109 125,426 29,154 30.28 9,693 44.55 0.0147
2022-11-14 2022-09-30 13F COSTAR GROUP COM 22160N109 96,272 19,050 24.67 6,705 43.73 0.0117
2022-08-04 2022-06-30 13F COSTAR GROUP COM 22160N109 77,222 68,029 740.01 4,665 661.01 0.0080
2022-05-09 2022-03-31 13F COSTAR GROUP COM 22160N109 9,193 5,319 137.30 613 100.33 0.0010
2022-02-03 2021-12-31 13F COSTAR GROUP COM 22160N109 3,874 -892 -18.72 306 -25.18 0.0005
2021-11-15 2021-09-30 13F COSTAR GROUP COM 22160N109 4,766 987 26.12 409 30.67 0.0007
2021-08-13 2021-06-30 13F COSTAR GROUP COM 22160N109 3,779 3,175 525.66 313 -36.90 0.0006
2021-05-14 2021-03-31 13F COSTAR GROUP COM 22160N109 604 61 11.23 496 -1.20 0.0011
2021-02-12 2020-12-31 13F COSTAR GROUP COM 22160N109 543 297 120.73 502 140.19 0.0012
2020-11-13 2020-09-30 13F COSTAR GROUP COM 22160N109 246 77 45.56 209 74.17 0.0006
2020-08-14 2020-06-30 13F COSTAR GROUP COM 22160N109 169 -65 -27.78 120 -12.41 0.0004
2020-05-08 2020-03-31 13F COSTAR GROUP COM 22160N109 234 3 1.30 137 -0.72 0.0005
2020-02-13 2019-12-31 13F COSTAR GROUP COM 22160N109 231 76 49.03 138 50.00 0.0005
2019-11-12 2019-09-30 13F COSTAR GROUP COM 22160N109 155 3 1.97 92 9.52 0.0003
2019-08-12 2019-06-30 13F COSTAR GROUP COM 22160N109 152 0 0.00 84 18.31 0.0003
2019-05-10 2019-03-31 13F COSTAR GROUP COM 22160N109 152 0 0.00 71 39.22 0.0003
2019-02-12 2018-12-31 13F COSTAR GROUP COM 22160N109 152 30 24.59 51 0.00 0.0003
2018-11-01 2018-09-30 13F COSTAR GROUP COM 22160N109 122 7 6.09 51 8.51 0.0003
2018-08-10 2018-06-30 13F COSTAR GROUP COM 22160N109 115 -2 -1.71 47 9.30 0.0003
2018-05-14 2018-03-31 13F COSTAR GROUP COM 22160N109 117 2 1.74 43 26.47 0.0003
2018-01-31 2017-12-31 13F COSTAR GROUP COM 22160N109 115 -50 -30.30 34 -22.73 0.0002
2017-11-07 2017-09-30 13F COSTAR GROUP COM 22160N109 165 0 0.00 44 2.33 0.0003
2017-08-10 2017-06-30 13F COSTAR GROUP COM 22160N109 165 -3 -1.79 43 22.86 0.0003
2017-05-09 2017-03-31 13F COSTAR GROUP COM 22160N109 168 -52 -23.64 35 -14.63 0.0003
2017-02-15 2016-12-31 13F COSTAR GROUP COM 22160N109 220 1 0.46 41 -14.58 0.0004
2016-11-14 2016-09-30 13F COSTAR GROUP COM 22160N109 219 8 3.79 48 4.35 0.0007
2016-08-29 2016-06-30 13F COSTAR GROUP COM 22160N109 211 50 31.06 46 53.33 0.0007
2016-05-16 2016-03-31 13F COSTAR GROUP COM 22160N109 161 38 30.89 30 20.00 0.0005
2016-02-16 2015-12-31 13F COSTAR GROUP COM 22160N109 123 10 8.85 25 25.00 0.0005
2015-11-16 2015-09-30 13F COSTAR GROUP COM 22160N109 113 -9 -7.38 20 -16.67 0.0005
2015-09-30 2015-06-30 13F/A-1 COSTAR GROUP COM 22160N109 122 -14 -10.29 24 -11.11 0.0006
2015-08-14 2015-06-30 13F COSTAR GROUP COM 22160N109 136 27
2015-05-15 2015-03-31 13F COSTAR GROUP COM 22160N109 136 49 56.32 27 68.75 0.0008
2015-02-13 2014-12-31 13F COSTAR GROUP COM 22160N109 87 34 64.15 16 100.00 0.0005
2014-11-14 2014-09-30 13F COSTAR GROUP COM 22160N109 53 -77 -59.23 8 -61.90 0.0003
2014-08-05 2014-06-30 13F COSTAR GROUP COM 22160N109 130 103 381.48 21 320.00 0.0008
2014-02-14 2013-12-31 13F COSTAR GROUP COM 22160N109 27 19 237.50 5 400.00 0.0002
2013-08-21 2013-06-30 13F/A-1 COSTAR GROUP COM 22160N109 8 8 1 0.0001
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.