CoStar Group, Inc.
MX ˙ BMV ˙ US22160N1090
DETTE SYMBOL ER IKKE LÆNGERE AKTIVT
SecurityMX:CSGP / CoStar Group, Inc.
InstitutionConestoga Capital Advisors, LLC
Latest Disclosed Ownership7,859 shares
Latest Disclosed Value $ 317,032
Conestoga Capital Advisors, LLC reports 35.99% decrease in ownership of CSGP / CoStar Group, Inc.

On April 24, 2026 - Conestoga Capital Advisors, LLC filed a 13F-HR form disclosing ownership of 7,859 shares of CoStar Group, Inc. (MX:CSGP) valued at $317,032 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 2, 2026 disclosing 12,277 shares of CoStar Group, Inc.. This represents a change in shares of -35.99% 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)
2026-04-24 2026-03-31 13F COSTAR GROUP COM 22160N109 7,859 -4,418 -35.99 317 -61.58 0.0063
2026-02-02 2025-12-31 13F COSTAR GROUP COM 22160N109 12,277 -3,263 -21.00 826 -37.07 0.0139
2025-10-24 2025-09-30 13F COSTAR GROUP COM 22160N109 15,540 50 0.32 1,311 5.30 0.0210
2025-07-30 2025-06-30 13F COSTAR GROUP COM 22160N109 15,490 -5 -0.03 1,245 1.47 0.0184
2025-04-17 2025-03-31 13F COSTAR GROUP COM 22160N109 15,495 310 2.04 1,228 12.88 0.0185
2025-01-24 2024-12-31 13F COSTAR GROUP COM 22160N109 15,185 0 0.00 1,087 -5.07 0.0144
2024-10-28 2024-09-30 13F COSTAR GROUP COM 22160N109 15,185 -405 -2.60 1,146 -0.87 0.0155
2024-07-26 2024-06-30 13F COSTAR GROUP COM 22160N109 15,590 -65 -0.42 1,156 -23.61 0.0173
2024-04-26 2024-03-31 13F COSTAR GROUP COM 22160N109 15,655 45 0.29 1,512 10.85 0.0219
2024-01-26 2023-12-31 13F COSTAR GROUP COM 22160N109 15,610 -220 -1.39 1,364 12.08 0.0205
2023-10-30 2023-09-30 13F COSTAR GROUP COM 22160N109 15,830 1,460 10.16 1,217 -4.77 0.0209
2023-07-28 2023-06-30 13F COSTAR GROUP COM 22160N109 14,370 -1,386 -8.80 1,279 17.90 0.0203
2023-04-24 2023-03-31 13F COSTAR GROUP COM 22160N109 15,756 -370 -2.29 1,085 -13.00 0.0182
2023-02-01 2022-12-31 13F COSTAR GROUP COM 22160N109 16,126 0 0.00 1,246 10.95 0.0233
2022-10-24 2022-09-30 13F COSTAR GROUP COM 22160N109 16,126 -189 -1.16 1,123 13.89 0.0220
2022-07-22 2022-06-30 13F COSTAR GROUP COM 22160N109 16,315 -495 -2.94 986 -11.96 0.0179
2022-04-25 2022-03-31 13F COSTAR GROUP COM 22160N109 16,810 -120 -0.71 1,120 -16.29 0.0169
2022-01-21 2021-12-31 13F COSTAR GROUP COM 22160N109 16,930 -275 -1.60 1,338 -9.66 0.0174
2021-10-22 2021-09-30 13F COSTAR GROUP COM 22160N109 17,205 960 5.91 1,481 10.11 0.0205
2021-07-27 2021-06-30 13F COSTAR GROUP COM 22160N109 16,245 14,755 990.27 1,345 9.80 0.0194
2021-04-23 2021-03-31 13F COSTAR GROUP COM 22160N109 1,490 -15 -1.00 1,225 -11.93 0.0185
2021-01-26 2020-12-31 13F COSTAR GROUP COM 22160N109 1,505 -100 -6.23 1,391 2.13 0.0222
2020-10-23 2020-09-30 13F COSTAR GROUP COM 22160N109 1,605 0 0.00 1,362 19.37 0.0275
2020-08-03 2020-06-30 13F COSTAR GROUP COM 22160N109 1,605 75 4.90 1,141 27.06 0.0248
2020-04-17 2020-03-31 13F COSTAR GROUP COM 22160N109 1,530 -75 -4.67 898 -6.46 0.0263
2020-01-24 2019-12-31 13F COSTAR GROUP COM 22160N109 1,605 -50 -3.02 960 -2.24 0.0231
2019-10-25 2019-09-30 13F COSTAR GROUP COM 22160N109 1,655 -6,287 -79.16 982 -77.68 0.0251
2019-08-02 2019-06-30 13F COSTAR GROUP COM 22160N109 7,942 -4,235 -34.78 4,400 -22.54 0.1100
2019-04-18 2019-03-31 13F COSTAR GROUP COM 22160N109 12,177 -2,548 -17.30 5,680 14.35 0.1581
2019-01-25 2018-12-31 13F COSTAR GROUP COM 22160N109 14,725 1,958 15.34 4,967 -7.56 0.1582
2018-10-25 2018-09-30 13F COSTAR GROUP COM 22160N109 12,767 2,225 21.11 5,373 23.52 0.1371
2018-07-20 2018-06-30 13F COSTAR GROUP COM 22160N109 10,542 -66,973 -86.40 4,350 -84.53 0.1401
2018-04-23 2018-03-31 13F COSTAR GROUP COM 22160N109 77,515 -6,689 -7.94 28,113 12.43 1.0766
2018-01-22 2017-12-31 13F COSTAR GROUP COM 22160N109 84,204 2,940 3.62 25,004 14.70 0.9601
2017-10-20 2017-09-30 13F COSTAR GROUP COM 22160N109 81,264 -32,156 -28.35 21,799 -27.09 0.9643
2017-07-21 2017-06-30 13F COSTAR GROUP COM 22160N109 113,420 1,950 1.75 29,898 29.43 1.5559
2017-04-19 2017-03-31 13F COSTAR GROUP COM 22160N109 111,470 4,564 4.27 23,099 14.63 1.3963
2017-01-11 2016-12-31 13F COSTAR GROUP COM 22160N109 106,906 400 0.38 20,151 -12.62 1.3417
2016-10-11 2016-09-30 13F COSTAR GROUP COM 22160N109 106,506 -35,050 -24.76 23,062 -25.49 1.5805
2016-07-22 2016-06-30 13F COSTAR GROUP COM 22160N109 141,556 -23,345 -14.16 30,953 -0.24 2.2869
2016-04-08 2016-03-31 13F COSTAR GROUP COM 22160N109 164,901 20,205 13.96 31,029 3.75 2.0960
2016-01-14 2015-12-31 13F COSTAR GROUP COM 22160N109 144,696 -29,977 -17.16 29,907 -1.07 2.4172
2015-10-16 2015-09-30 13F COSTAR GROUP COM 22160N109 174,673 -4,651 -2.59 30,229 -16.24 2.4230
2015-07-09 2015-06-30 13F COSTAR GROUP COM 22160N109 179,324 -4,825 -2.62 36,091 -0.93 2.5053
2015-04-28 2015-03-31 13F COSTAR GROUP COM 22160N109 184,149 -12,645 -6.43 36,430 0.81 2.4936
2015-01-12 2014-12-31 13F COSTAR GROUP COM 22160N109 196,794 -11,713 -5.62 36,137 11.43 2.5141
2014-11-07 2014-09-30 13F COSTAR GROUP COM 22160N109 208,507 -335 -0.16 32,431 -1.82 2.3690
2014-11-07 2014-06-30 13F/A-1 COSTAR GROUP COM 22160N109 208,842 -10,173 -4.64 33,033 -19.23 2.2163
2014-07-08 2014-06-30 13F COSTAR GROUP COM 22160N109 156,056 24,683
2014-11-07 2014-03-31 13F/A-1 COSTAR GROUP COM 22160N109 219,015 -89,544 -29.02 40,899 -28.19 2.5868
2014-04-23 2014-03-31 13F COSTAR GROUP COM 22160N109 179,367 33,495
2014-11-07 2013-12-31 13F/A-1 COSTAR GROUP COM 22160N109 308,559 629 0.20 56,954 10.15 3.8265
2014-01-22 2013-12-31 13F COSTAR GROUP COM 22160N109 276,147 50,971
2014-11-07 2013-09-30 13F/A-1 COSTAR GROUP COM 22160N109 307,930 -39,660 -11.41 51,705 15.25 4.4296
2013-10-23 2013-09-30 13F COSTAR GROUP COM 22160N109 304,318 51,099
2014-11-07 2013-06-30 13F/A-1 COSTAR GROUP COM 22160N109 347,590 -2,940 -0.84 44,863 16.93 4.6314
2013-07-29 2013-06-30 13F COSTAR GROUP COM 22160N109 346,463 44,718
2014-11-07 2013-03-31 13F/A-1 COSTAR GROUP COM 22160N109 350,530 350,530 38,369 4.0696
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.