CoStar Group, Inc.
MX ˙ BMV ˙ US22160N1090
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityMX:CSGP / CoStar Group, Inc.
InstitutionIronvine Capital Partners, LLC
Latest Disclosed Ownership375,331 shares
Latest Disclosed Value $ 15,140,853
Ironvine Capital Partners, LLC reports 1.11% increase in ownership of CSGP / CoStar Group, Inc.

On May 15, 2026 - Ironvine Capital Partners, LLC filed a 13F-HR form disclosing ownership of 375,331 shares of CoStar Group, Inc. (MX:CSGP) valued at $15,140,853 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 371,224 shares of CoStar Group, Inc.. This represents a change in shares of 1.11% 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)
2026-05-15 2026-03-31 13F COSTAR GROUP COM 22160N109 375,331 4,107 1.11 15,141 -39.35 1.6643
2026-02-13 2025-12-31 13F COSTAR GROUP COM 22160N109 371,224 -59,110 -13.74 24,961 -31.25 2.4987
2025-11-14 2025-09-30 13F COSTAR GROUP COM 22160N109 430,334 -10,080 -2.29 36,307 2.54 3.6140
2025-08-14 2025-06-30 13F COSTAR GROUP COM 22160N109 440,414 -17,544 -3.83 35,409 -2.41 3.6693
2025-05-15 2025-03-31 13F COSTAR GROUP COM 22160N109 457,958 -8,753 -1.88 36,284 8.60 3.9391
2025-02-14 2024-12-31 13F COSTAR GROUP COM 22160N109 466,711 -5,341 -1.13 33,412 -6.18 3.5800
2024-11-14 2024-09-30 13F COSTAR GROUP COM 22160N109 472,052 1,237 0.26 35,612 2.02 3.8231
2024-08-14 2024-06-30 13F COSTAR GROUP COM 22160N109 470,815 17,067 3.76 34,906 -20.36 3.8232
2024-05-15 2024-03-31 13F COSTAR GROUP COM 22160N109 453,748 1,392 0.31 43,832 10.88 4.8065
2024-02-14 2023-12-31 13F COSTAR GROUP COM 22160N109 452,356 -21,651 -4.57 39,531 8.46 4.7409
2023-11-14 2023-09-30 13F COSTAR GROUP COM 22160N109 474,007 1,558 0.33 36,446 -13.32 4.6764
2023-08-14 2023-06-30 13F COSTAR GROUP COM 22160N109 472,449 -4,259 -0.89 42,048 28.11 5.1055
2023-05-15 2023-03-31 13F COSTAR GROUP COM 22160N109 476,708 1,249 0.26 32,821 -10.67 4.1405
2023-02-14 2022-12-31 13F COSTAR GROUP COM 22160N109 475,459 -1,441 -0.30 36,743 10.62 4.7565
2022-11-14 2022-09-30 13F COSTAR GROUP COM 22160N109 476,900 21,011 4.61 33,216 20.61 4.4574
2022-08-15 2022-06-30 13F COSTAR GROUP COM 22160N109 455,889 11,392 2.56 27,540 -6.98 3.3803
2022-05-16 2022-03-31 13F COSTAR GROUP COM 22160N109 444,497 154,977 53.53 29,608 29.40 3.1932
2022-02-14 2021-12-31 13F COSTAR GROUP COM 22160N109 289,520 51,964 21.87 22,881 11.92 2.3477
2021-11-15 2021-09-30 13F COSTAR GROUP COM 22160N109 237,556 150,304 172.26 20,444 182.92 2.1710
2021-08-16 2021-06-30 13F COSTAR GROUP COM 22160N109 87,252 78,577 905.79 7,226 1.35 0.7915
2021-04-29 2021-03-31 13F COSTAR GROUP COM 22160N109 8,675 2,466 39.72 7,130 24.24 0.8299
2021-02-02 2020-12-31 13F COSTAR GROUP COM 22160N109 6,209 -2,492 -28.64 5,739 -22.27 0.7167
2020-11-03 2020-09-30 13F COSTAR GROUP COM 22160N109 8,701 1,608 22.67 7,383 46.46 0.9250
2020-08-05 2020-06-30 13F COSTAR GROUP COM 22160N109 7,093 7,093 5,041 0.6670
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.