California Water Service Group
US ˙ NYSE ˙ US1307881029

SecurityCWT / California Water Service Group
InstitutionNorthern Trust Corp
Latest Disclosed Ownership637,303 shares
Latest Disclosed Value $ 28,895,319
Northern Trust Corp reports 4.21% increase in ownership of CWT / California Water Service Group

On May 14, 2026 - Northern Trust Corp filed a 13F-HR form disclosing ownership of 637,303 shares of California Water Service Group (US:CWT) valued at $28,895,318 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 611,552 shares of California Water Service Group. This represents a change in shares of 4.21% during the quarter. The current value of the position is $28,831,588 USD.

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)
2026-05-14 2026-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 637,303 25,751 4.21 28,895 9.05 0.0008
2026-02-17 2025-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 611,552 -43,702 -6.67 26,499 -11.88 0.0007
2025-11-14 2025-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 655,254 -58,128 -8.15 30,070 -7.32 0.0009
2025-08-13 2025-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 713,382 -259,095 -26.64 32,445 -31.15 0.0045
2025-05-13 2025-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 972,477 -6,661 -0.68 47,126 6.18 0.0070
2025-02-14 2024-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 979,138 113,622 13.13 44,384 -5.42 0.0063
2024-11-13 2024-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 865,516 -84,517 -8.90 46,928 1.87 0.0077
2024-08-14 2024-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 950,033 -34,787 -3.53 46,067 0.64 0.0078
2024-05-14 2024-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 984,820 21,208 2.20 45,774 -8.42 0.0079
2024-02-13 2023-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 963,612 -61,293 -5.98 49,983 3.08 0.0090
2023-11-13 2023-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 1,024,905 43,285 4.41 48,488 -4.33 0.0094
2023-08-11 2023-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 981,620 26,869 2.81 50,681 -8.79 0.0097
2023-05-15 2023-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 954,751 -17,083 -1.76 55,567 -5.71 0.0110
2023-02-13 2022-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 971,834 66,931 7.40 58,932 23.60 0.0124
2022-11-14 2022-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 904,903 -25,475 -2.74 47,679 -7.75 0.0109
2022-08-12 2022-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 930,378 -55,305 -5.61 51,682 -11.55 0.0111
2022-05-13 2022-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 985,683 50,908 5.45 58,431 -13.01 0.0103
2022-02-08 2021-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 934,775 21,649 2.37 67,173 24.83 0.0110
2021-11-15 2021-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 913,126 75,401 9.00 53,810 15.65 0.0095
2021-08-13 2021-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 837,725 -12,119 -1.43 46,527 -2.83 0.0082
2021-05-12 2021-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 849,844 38,874 4.79 47,880 9.27 0.0089
2021-02-11 2020-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 810,970 -9,792 -1.19 43,817 22.87 0.0085
2020-11-16 2020-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 820,762 -28,898 -3.40 35,662 -12.01 0.0078
2020-08-14 2020-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 849,660 50,199 6.28 40,528 0.74 0.0096
2020-05-14 2020-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 799,461 -495 -0.06 40,229 -2.47 0.0115
2020-02-14 2019-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 799,956 -31,986 -3.84 41,246 -6.33 0.0092
2019-11-13 2019-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 831,942 25,953 3.22 44,034 7.91 0.0105
2019-08-13 2019-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 805,989 6,934 0.87 40,807 -5.92 0.0097
2019-05-13 2019-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 799,055 28,514 3.70 43,373 18.11 0.0107
2019-02-12 2018-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 770,541 -26,411 -3.31 36,724 7.42 0.0103
2018-11-14 2018-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 796,952 195 0.02 34,188 10.16 0.0084
2018-09-18 2018-06-30 13F/A-1 CALIFORNIA WTR SVC GROUP COM 130788102 796,757 -3,160 -0.40 31,034 4.15 0.0079
2018-08-14 2018-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 799,874 -43 31,155
2018-05-09 2018-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 799,917 43,225 5.71 29,796 -13.17 0.0078
2018-02-14 2017-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 756,692 -8,506 -1.11 34,317 17.56 0.0087
2017-11-13 2017-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 765,198 18,635 2.50 29,192 6.26 0.0076
2017-08-11 2017-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 746,563 12,513 1.70 27,473 4.40 0.0077
2017-05-12 2017-03-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 734,050 21,812 3.06 26,315 8.99 0.0076
2017-02-13 2016-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 712,238 124,116 21.10 24,145 27.94 0.0074
2016-11-09 2016-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 588,122 -91,089 -13.41 18,872 -20.46 0.0059
2016-08-12 2016-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 679,211 46,454 7.34 23,725 42.85 0.0077
2016-08-19 2016-03-31 13F/A-1 CALIFORNIA WTR SVC GROUP COM 130788102 632,757 57,023 9.90 16,608 23.96 0.0055
2016-05-13 2016-03-31 13F California Wtr Svc G COMM 130788102 632,754 16,908
2016-02-12 2015-12-31 13F California Wtr Svc G COMM 130788102 575,734 43,679 8.21 13,398 13.84 0.0044
2015-11-12 2015-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 532,055 19,842 3.87 11,769 0.56 0.0039
2015-08-13 2015-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 512,213 -24,079 -4.49 11,703 -10.96 0.0079
2015-08-13 2015-06-30 13F California Wtr Svc G COMM 013078810 7,259 -529,033 166 0.0001
2015-05-14 2015-03-31 13F California Wtr Svc G COMM 130788102 536,292 16,878 3.25 13,144 2.82 0.0040
2015-02-12 2014-12-31 13F California Wtr Svc G COM 130788102 519,414 -28,896 -5.27 12,783 3.88 0.0039
2014-11-13 2014-09-30 13F California Wtr Svc G COMM 130788102 548,310 -36,126 -6.18 12,305 -13.00 0.0039
2014-08-14 2014-06-30 13F CALIFORNIA WTR SVC GROUP com 130788102 584,436 -52,512 -8.24 14,143 -7.25 0.0044
2014-05-14 2014-03-31 13F CALIFORNIA WTR SVC GROUP COMM 130788102 636,948 -36,953 -5.48 15,249 -1.91 0.0048
2014-02-21 2013-12-31 13F/A-1 CALIFORNIA WTR SVC GROUP COM 130788102 673,901 21,598 3.31 15,546 17.28 0.0050
2014-02-12 2013-12-31 13F CALIFORNIA WTR SVC GROUP COM 130788102 673,901 15,546
2013-11-13 2013-09-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 652,303 -19,726 -2.94 13,255 1.10 0.0047
2013-08-09 2013-06-30 13F CALIFORNIA WTR SVC GROUP COM 130788102 672,029 672,029 13,111 0.0048
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.