CoStar Group, Inc.
MX ˙ BMV ˙ US22160N1090
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityMX:CSGP / CoStar Group, Inc.
InstitutionAssenagon Asset Management S.A.
Latest Disclosed Ownership8,599 shares
Latest Disclosed Value $ 346,884
Assenagon Asset Management S.A. reports 24.97% decrease in ownership of CSGP / CoStar Group, Inc.

On April 20, 2026 - Assenagon Asset Management S.A. filed a 13F-HR form disclosing ownership of 8,599 shares of CoStar Group, Inc. (MX:CSGP) valued at $346,884 USD as of March 31, 2026. The entity filed a previous 13F-HR on January 9, 2026 disclosing 11,461 shares of CoStar Group, Inc.. This represents a change in shares of -24.97% 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)
2026-04-20 2026-03-31 13F COSTAR GROUP COM 22160N109 8,599 -2,862 -24.97 347 -55.06 0.0005
2026-01-09 2025-12-31 13F COSTAR GROUP COM 22160N109 11,461 -1,536 -11.82 771 -29.74 0.0011
2025-10-07 2025-09-30 13F COSTAR GROUP COM 22160N109 12,997 4,833 59.20 1,097 67.07 0.0015
2025-07-11 2025-06-30 13F COSTAR GROUP COM 22160N109 8,164 214 2.69 656 4.29 0.0010
2025-04-15 2025-03-31 13F COSTAR GROUP COM 22160N109 7,950 -393,416 -98.02 630 -97.81 0.0011
2025-01-14 2024-12-31 13F COSTAR GROUP COM 22160N109 401,366 113,925 39.63 28,734 32.51 0.0463
2024-10-23 2024-09-30 13F COSTAR GROUP COM 22160N109 287,441 -81,850 -22.16 21,685 -20.80 0.0399
2024-07-18 2024-06-30 13F COSTAR GROUP COM 22160N109 369,291 263,234 248.20 27,379 167.24 0.0609
2024-04-24 2024-03-31 13F COSTAR GROUP COM 22160N109 106,057 -63,297 -37.38 10,245 -30.77 0.0243
2024-01-17 2023-12-31 13F COSTAR GROUP COM 22160N109 169,354 74,375 78.31 14,800 102.67 0.0393
2023-11-06 2023-09-30 13F COSTAR GROUP COM 22160N109 94,979 -292,134 -75.46 7,303 -78.81 0.0226
2023-07-25 2023-06-30 13F COSTAR GROUP COM 22160N109 387,113 375,812 3,325.48 34,453 4,328.41 0.1192
2023-04-18 2023-03-31 13F COSTAR GROUP COM 22160N109 11,301 -31,225 -73.43 778 25,833.33 0.0028
2023-01-12 2022-12-31 13F COSTAR GROUP COM 22160N109 42,526 -1,195 -2.73 3 -99.90 0.0119
2022-10-27 2022-09-30 13F COSTAR GROUP COM 22160N109 43,721 -238,394 -84.50 3,045 -82.13 0.0117
2022-07-27 2022-06-30 13F COSTAR GROUP COM 22160N109 282,115 -1,039,692 -78.66 17,043 -80.64 0.0632
2022-04-25 2022-03-31 13F COSTAR GROUP COM 22160N109 1,321,807 789,162 148.16 88,046 109.16 0.2446
2022-02-01 2021-12-31 13F COSTAR GROUP COM 22160N109 532,645 201,066 60.64 42,095 47.52 0.1219
2021-10-19 2021-09-30 13F COSTAR GROUP COM 22160N109 331,579 331,579 28,536 0.0913
2021-07-15 2021-06-30 13F COSTAR GROUP COM 22160N109 0 -28,929 -100.00 0 -100.00
2021-04-26 2021-03-31 13F COSTAR GROUP COM 22160N109 28,929 26,020 894.47 23,776 784.19 0.0965
2021-02-01 2020-12-31 13F COSTAR GROUP COM 22160N109 2,909 2,909 2,689 0.0117
2020-10-07 2020-09-30 13F COSTAR GROUP COM 22160N109 0 -138,114 -100.00 0 -100.00
2020-07-21 2020-06-30 13F COSTAR GROUP COM 22160N109 138,114 97,136 237.04 98,153 307.90 0.6295
2020-04-17 2020-03-31 13F COSTAR GROUP COM 22160N109 40,978 40,978 24,063 0.1926
2020-01-17 2019-12-31 13F COSTAR GROUP COM 22160N109 0 -28,583 -100.00 0 -100.00
2019-10-16 2019-09-30 13F COSTAR GROUP COM 22160N109 28,583 -82,121 -74.18 16,955 -72.36 0.1135
2019-08-12 2019-06-30 13F COSTAR GROUP COM 22160N109 110,704 110,232 23,354.24 61,337 27,780.45 0.4607
2019-04-26 2019-03-31 13F COSTAR GROUP COM 22160N109 472 472 220 0.0021
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.