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CoStar Group

CSGP Net selling
CIK 0001057352 #134 in the set updated 17 Sep 2026
Bought (120 mo)
$9.58M
out of their own pocket, the only kind of buying there is
Sold (120 mo)
$359.73M
$0.00 on a plan · $231.44M straight out of an exercise
Sold at will
$128.29M
73 of 100 sales
Net
−$350.14M
−$118.70M against sales at will

By person

24 insiders · 118 transactions
55.5×

Andrew C. Florance holds 55.5 times base salary in stock. $55.59M of shares against $1.00M in salary for 2025.

Salary from the company's own proxy. The shares are what Andrew C. Florance last reported holding, valued at $30.78, the price Common Stock, par value $0.01 per share was last bought or sold at on the open market here, on 7 Aug 2026.

Insider
Role
Bought
Sold
Net
Holding
Of company
Worth
Change
FLORANCE ANDREW C
Founder and CEO
$8.58M (5)
$186.93M (14) scheduled
−$178.35M
1,806,165
0.4457%
$55.59M
+133.2%
Wheeler Scott T
Chief Financial Officer
—
$45.17M (12) scheduled
−$45.17M
304,958
0.0753%
$9.39M
+25.0%
KLEIN MICHAEL R
Director
—
$38.50M (7)
−$38.50M
1,848,592
0.4562%
$56.90M
−23.0%
CARCHEDI FRANCIS
Executive VP, Corp. Dev.
—
$20.86M (5) scheduled
−$20.86M
6,540
0.0016%
$201.30K
−72.7%
Linnington Matthew
Executive VP, Sales
—
$18.78M (9) scheduled
−$18.78M
19,766
0.0049%
$608.40K
−8.1%
SAINT FREDERICK G.
President, Marketplaces
$906.60K (1)
$15.76M (6)
−$14.85M
278,415
0.0687%
$8.57M
+18.5%
Ruggles Lisa
Senior VP, Global Operations
—
$13.23M (5)
−$13.23M
174,915
0.0432%
$5.38M
+18.6%
SIMURO FRANK
Chief Technology Officer
—
$10.74M (2)
−$10.74M
414,491
0.1023%
$12.76M
+38.7%
Hill John W
Director
—
$4.28M (17)
−$4.28M
22,993
0.0057%
$707.72K
−39.4%
Kaplan Laura Cox
Director
—
$1.60M (3)
−$1.60M
17,835
0.0044%
$548.96K
+114.2%
DESMARAIS MICHAEL J
Chief Human Resources Officer
—
$1.50M (6)
−$1.50M
87,725
0.0216%
$2.70M
+87.4%
NASSETTA CHRISTOPHER J
Director
—
$967.73K (7)
−$967.73K
275,715
0.0680%
$8.49M
+3.6%
Cann Cynthia Cammett
Chief Accounting Officer
—
$797.04K (6)
−$797.04K
18,822
0.0046%
$579.34K
−3.9%
Steinberg David Jay
Director
—
$606.90K (1)
−$606.90K
6,456
0.0016%
$198.72K
+10.5%
Sams Louise S
Director
$48.36K (1)
—
+$48.36K
28,671
0.0071%
$882.49K
+1,273%
Glaser Rachel C
Director
$44.94K (1)
—
+$44.94K
12,419
0.0031%
$382.26K
+88,607%
LOWN CHRISTIAN M.
Chief Financial Officer
—
—
—
129,653
0.0320%
$3.99M
+3,731%
HABER WARREN H
Director
—
—
—
121,049
0.0299%
$3.73M
+1.0%
Glosserman Michael J
Director
—
—
—
101,465
0.0250%
$3.12M
+12.9%
Boxer Gene
General Counsel and Secretary
—
—
—
95,517
0.0236%
$2.94M
+2,139%
Musslewhite Robert W
Director
—
—
—
26,539
0.0065%
$816.87K
+1,278%
Brunner Angelique G.
Director
—
—
—
18,428
0.0045%
$567.21K
—
McCarthy Christine M
Director
—
—
—
11,585
0.0029%
$356.59K
+3,210%
BERISFORD JOHN L
Director
—
—
—
11,235
0.0028%
$345.81K
—

Individual transactions

118
Insider
Date
Role
Action
Shares
Price
Amount
Cann Cynthia Cammett
7 Aug 2026
Chief Accounting Officer
Sell
4,788
$30.78
$147.37K
Hill John W
5 Aug 2026
Director
Sell
3,500
$30.21
$105.74K
FLORANCE ANDREW C
4 Aug 2026
Founder and CEO
Buy
83,300
$29.89
$2.49M
FLORANCE ANDREW C
1 May 2026
President and CEO
Buy
3,100
$35.82
$111.04K
FLORANCE ANDREW C
1 May 2026
President and CEO
Buy
68,330
$35.17
$2.40M
Sams Louise S
6 Mar 2026
Director
Buy
1,000
$48.36
$48.36K
SAINT FREDERICK G.
2 Mar 2026
President, Marketplaces
Buy
20,000
$45.33
$906.60K
Glaser Rachel C
2 Mar 2026
Director
Buy
1,000
$44.94
$44.94K
FLORANCE ANDREW C
27 Feb 2026
President and CEO
Buy
55,720
$44.52
$2.48M
Cann Cynthia Cammett
13 Nov 2025
Chief Accounting Officer
Sell
1,841
$68.79
$126.64K
Hill John W
13 Nov 2025
Director
Sell
2,250
$68.68
$154.53K
SAINT FREDERICK G.
28 Aug 2025
President, Marketplaces
Sell
25,000
$90.33
$2.26M
Cann Cynthia Cammett
28 Jul 2025
Chief Accounting Officer
Sell
2,033
$92.85
$188.76K
SAINT FREDERICK G.
28 Jul 2025
President, Marketplaces
Sell
25,000
$93.23
$2.33M
SAINT FREDERICK G.
11 Jun 2025
President, Marketplaces
Sell
25,000
$81.10
$2.03M
Cann Cynthia Cammett
10 Mar 2025
Chief Accounting Officer
Sell
1,749
$79.90
$139.75K
Hill John W
10 Dec 2024
Director
Sell
2,735
$76.76
$209.94K
NASSETTA CHRISTOPHER J
27 Nov 2024
Director
Sell
1,681
$80.39
$135.14K
DESMARAIS MICHAEL J
26 Nov 2024
Chief Human Resources Officer
Sell
5,500
$79.88
$439.34K
Cann Cynthia Cammett
11 Nov 2024
Chief Accounting Officer
Sell
1,310
$76.85
$100.67K
FLORANCE ANDREW C
25 Oct 2024
President and CEO
Buy
14,731
$74.67
$1.10M
KLEIN MICHAEL R
25 Oct 2024
Director
Sell
71,633
$74.69
$5.35M
Cann Cynthia Cammett
31 Jul 2024
Chief Accounting Officer
Sell
1,200
$78.20
$93.84K
Hill John W
30 Jul 2024
Director
Sell
1,325
$78.16
$103.56K
SAINT FREDERICK G.
16 May 2024
President, Marketplaces
Sell
2,500
$88.43
$221.08K
Ruggles Lisa
9 May 2024
Senior VP, Global Operations
Sell
20,000
$91.15
$1.82M
Wheeler Scott T
26 Apr 2024
Chief Financial Officer
Sold after exercise
122,736
$92.61
$11.37M
DESMARAIS MICHAEL J
26 Apr 2024
Chief Human Resources Officer
Sell
3,800
$92.67
$352.15K
Hill John W
28 Nov 2023
Director
Sell
3,020
$84.07
$253.89K
NASSETTA CHRISTOPHER J
8 Nov 2023
Director
Sell
1,500
$77.86
$116.79K
Ruggles Lisa
30 Jun 2023
Senior VP, Global Research
Sell
30,474
$91.42
$2.79M
Wheeler Scott T
28 Jun 2023
Chief Financial Officer
Sell
21,530
$89.30
$1.92M
SIMURO FRANK
27 Jun 2023
Chief Technology Officer
Sell
92,300
$89.65
$8.27M
Hill John W
26 Jun 2023
Director
Sell
1,500
$86.57
$129.86K
Wheeler Scott T
12 Jun 2023
Chief Financial Officer
Sell
24,670
$80.68
$1.99M
SAINT FREDERICK G.
7 Jun 2023
President, Marketplaces
Sell
30,000
$80.24
$2.41M
FLORANCE ANDREW C
28 Apr 2023
President and CEO
Sold after exercise
360,530
$76.77
$27.68M
Hill John W
31 Mar 2023
Director
Sell
2,300
$68.50
$157.55K
SIMURO FRANK
17 Mar 2023
Chief Technology Officer
Exercised, kept
2,920
$34.21
$99.89K
SIMURO FRANK
17 Mar 2023
Chief Technology Officer
Exercised, kept
4,880
$20.49
$99.99K
SIMURO FRANK
17 Mar 2023
Chief Technology Officer
Exercised, kept
5,470
$18.28
$99.99K
SIMURO FRANK
17 Mar 2023
Chief Technology Officer
Exercised, kept
10,320
$19.37
$199.90K
DESMARAIS MICHAEL J
8 Mar 2023
Chief Human Resources Officer
Sell
5,600
$70.36
$394.02K
SIMURO FRANK
1 Mar 2023
Chief Technology Officer
Sold after exercise
35,220
$70.09
$2.47M
Hill John W
3 Nov 2022
Director
Sell
3,650
$78.92
$288.06K
DESMARAIS MICHAEL J
28 Oct 2022
Chief Human Resources Officer
Sell
1,296
$82.81
$107.32K
Hill John W
10 Aug 2022
Director
Sell
1,400
$74.49
$104.29K
KLEIN MICHAEL R
5 Aug 2022
Director
Sell
150,000
$72.42
$10.86M
DESMARAIS MICHAEL J
3 Aug 2022
Chief Human Resources Officer
Sell
2,000
$72.51
$145.02K
Hill John W
24 May 2022
Director
Sell
1,750
$57.07
$99.87K
DESMARAIS MICHAEL J
2 May 2022
Chief Human Resources Officer
Sell
1,000
$63.14
$63.14K
Ruggles Lisa
2 Mar 2022
Senior VP, Global Research
Sell
21,640
$59.88
$1.30M
Wheeler Scott T
11 Nov 2021
Chief Financial Officer
Sell indirect
85
$81.72
$6.95K
NASSETTA CHRISTOPHER J
10 Nov 2021
Director
Sell
2,120
$83.21
$176.41K
Kaplan Laura Cox
5 Nov 2021
Director
Sell
4,040
$83.29
$336.49K
Hill John W
29 Oct 2021
Director
Sell
9,235
$86.97
$803.17K
Hill John W
9 Aug 2021
Director
Sell
6,160
$85.77
$528.31K
Kaplan Laura Cox
30 Apr 2021
Director
Sell
1,062
$869.03
$922.91K
SAINT FREDERICK G.
23 Mar 2021
President, Marketplaces
Sold after exercise
7,834
$831.70
$6.52M
Wheeler Scott T
16 Mar 2021
Chief Financial Officer
Sold after exercise
7,326
$843.28
$6.18M
FLORANCE ANDREW C
10 Mar 2021
President and CEO
Sell
19,570
$818.37
$16.02M
Ruggles Lisa
2 Sep 2020
Senior VP, Global Research
Sold after exercise
7,596
$870.00
$6.61M
FLORANCE ANDREW C
27 Aug 2020
President and CEO
Sold after exercise
15,584
$851.66
$13.27M
FLORANCE ANDREW C
26 Aug 2020
President and CEO
Sold after exercise
15,584
$848.16
$13.22M
Linnington Matthew
12 Aug 2020
Executive VP, Sales
Sell
2,419
$826.32
$2.00M
Wheeler Scott T
4 Aug 2020
Chief Financial Officer
Sold after exercise
12,002
$826.71
$9.92M
KLEIN MICHAEL R
7 May 2020
Director
Sell
11,361
$636.51
$7.23M
KLEIN MICHAEL R
6 May 2020
Director
Sell
3,639
$647.52
$2.36M
Steinberg David Jay
4 Mar 2020
Director
Sell
850
$714.00
$606.90K
Wheeler Scott T
3 Mar 2020
Chief Financial Officer
Sold after exercise
6,005
$703.26
$4.22M
FLORANCE ANDREW C
2 Mar 2020
President and CEO
Sold after exercise
33,600
$663.90
$22.31M
Wheeler Scott T
29 Feb 2020
Chief Financial Officer
Exercised, kept
3,600
$342.13
$1.23M
FLORANCE ANDREW C
31 Dec 2019
President and CEO
Exercised, kept
547
$182.75
$99.96K
FLORANCE ANDREW C
31 Dec 2019
President and CEO
Exercised, kept
1,032
$193.69
$199.89K
Hill John W
31 Dec 2019
Director
Sell
500
$591.90
$295.95K
Kaplan Laura Cox
19 Nov 2019
Director
Sell
576
$591.60
$340.76K
NASSETTA CHRISTOPHER J
25 Oct 2019
Director
Sell
406
$570.99
$231.82K
Linnington Matthew
31 Jul 2019
Executive VP, Sales
Sold after exercise
14,651
$617.39
$9.05M
FLORANCE ANDREW C
26 Jul 2019
President and CEO
Sell
24,210
$628.64
$15.22M
Wheeler Scott T
26 Jul 2019
Chief Financial Officer
Sold after exercise
6,933
$629.50
$4.36M
Hill John W
24 Jun 2019
Director
Sell
315
$553.23
$174.27K
FLORANCE ANDREW C
4 Mar 2019
President and CEO
Sold after exercise
55,322
$473.38
$26.19M
Wheeler Scott T
1 Mar 2019
Chief Financial Officer
Sell
5,396
$476.11
$2.57M
Linnington Matthew
1 Mar 2019
Executive VP, Sales
Sold after exercise
4,701
$477.31
$2.24M
Ruggles Lisa
1 Mar 2019
Senior VP, Global Research
Sell
1,538
$466.62
$717.66K
Hill John W
26 Dec 2018
Director
Sell
1,042
$330.88
$344.78K
NASSETTA CHRISTOPHER J
29 Oct 2018
Director
Sell
571
$349.67
$199.66K
KLEIN MICHAEL R
6 Aug 2018
Director
Sell
15,000
$420.69
$6.31M
Linnington Matthew
30 Jul 2018
Executive VP, Sales
Sold after exercise
4,384
$411.93
$1.81M
CARCHEDI FRANCIS
27 Jul 2018
Executive VP, Corp. Dev.
Sold after exercise
32,671
$421.87
$13.78M
Wheeler Scott T
27 Jul 2018
Chief Financial Officer
Sold after exercise
4,700
$426.02
$2.00M
FLORANCE ANDREW C
30 Apr 2018
President and CEO
Sell
5,839
$369.05
$2.15M
FLORANCE ANDREW C
27 Apr 2018
President and CEO
Sell
11,200
$371.15
$4.16M
FLORANCE ANDREW C
26 Apr 2018
President and CEO
Sell
7,782
$372.34
$2.90M
Hill John W
29 Mar 2018
Director
Sell
1,150
$361.28
$415.47K
KLEIN MICHAEL R
22 Mar 2018
Director
Sell
3,000
$361.61
$1.08M
CARCHEDI FRANCIS
7 Mar 2018
Executive VP, Corp. Dev.
Sold after exercise
12,100
$356.09
$4.31M
Wheeler Scott T
5 Mar 2018
Chief Financial Officer
Sell
1,250
$353.69
$442.11K
Linnington Matthew
2 Mar 2018
Executive VP, Sales
Sold after exercise
1,153
$348.45
$401.76K
Linnington Matthew
2 Mar 2018
Executive VP, Sales
Sold after exercise
6,768
$348.19
$2.36M
FLORANCE ANDREW C
27 Feb 2018
President and CEO
Sold after exercise
80,055
$347.10
$27.79M
Linnington Matthew
31 Jul 2017
Executive VP, Sales
Sold after exercise
1,767
$273.15
$482.66K
KLEIN MICHAEL R
26 Jun 2017
Director
Sell
20,000
$265.01
$5.30M
FLORANCE ANDREW C
3 May 2017
President and CEO
Sold after exercise
21,768
$244.19
$5.32M
FLORANCE ANDREW C
2 May 2017
President and CEO
Sold after exercise
21,768
$244.73
$5.33M
CARCHEDI FRANCIS
2 May 2017
Executive VP, Corp. Dev.
Sold after exercise
5,500
$245.04
$1.35M
Hill John W
2 May 2017
Director
Sell
440
$244.52
$107.59K
Linnington Matthew
1 May 2017
Executive VP, Sales
Sell
1,037
$240.00
$248.88K
Wheeler Scott T
1 May 2017
Chief Financial Officer
Sell
757
$240.00
$181.68K
CARCHEDI FRANCIS
6 Mar 2017
Executive VP, Corp. Dev.
Sell
2,448
$205.30
$502.57K
FLORANCE ANDREW C
2 Mar 2017
President and CEO
Sell
26,271
$205.31
$5.39M
CARCHEDI FRANCIS
2 Mar 2017
Executive VP, Corp. Dev.
Sold after exercise
4,500
$204.98
$922.41K
FLORANCE ANDREW C
29 Dec 2016
President and CEO
Exercised, kept
978
$102.16
$99.91K
FLORANCE ANDREW C
29 Dec 2016
President and CEO
Exercised, kept
1,696
$58.95
$99.98K
FLORANCE ANDREW C
29 Dec 2016
President and CEO
Exercised, kept
499
$57.16
$28.52K
NASSETTA CHRISTOPHER J
1 Nov 2016
Director
Sell
75
$187.30
$14.05K
Linnington Matthew
31 Oct 2016
Executive VP, Sales
Sell
1,060
$188.31
$199.61K
NASSETTA CHRISTOPHER J
31 Oct 2016
Director
Sell
500
$187.73
$93.87K

What was left out

Form 4 filings counted 388
Amendments (4/A) skipped 2
Filings about a different issuer 0
Unreadable filings 0
Joint filings 0
Sales on a Rule 10b5-1 plan 0
Sales straight out of an exercise 27
Sales at will 73
Transactions with no price 0
Shares from compensation/vesting 6,159,955
Sales filed before the plan box existed 45
History held since 13 Sep 2016