Middlesex Water Company
US ˙ NasdaqGS ˙ US5966801087

SecurityMSEX / Middlesex Water Company
InstitutionD. E. Shaw & Co., Inc.
ManagerDE Shaw
Latest Disclosed Ownership26,403 shares
Latest Disclosed Value $ 1,374,276
D. E. Shaw & Co., Inc. reports 30.33% increase in ownership of MSEX / Middlesex Water Company

On May 15, 2026 - D. E. Shaw & Co., Inc. filed a 13F-HR form disclosing ownership of 26,403 shares of Middlesex Water Company (US:MSEX) valued at $1,374,276 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 20,259 shares of Middlesex Water Company. This represents a change in shares of 30.33% during the quarter. The current value of the position is $1,371,108 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)
2026-05-15 2026-03-31 13F MIDDLESEX WTR COM 596680108 26,403 6,144 30.33 1,374 34.57 0.0008
2026-02-17 2025-12-31 13F MIDDLESEX WTR COM 596680108 20,259 -56,463 -73.59 1,021 -75.41 0.0006
2025-11-14 2025-09-30 13F MIDDLESEX WTR COM 596680108 76,722 3,423 4.67 4,152 4.56 0.0023
2025-08-14 2025-06-30 13F MIDDLESEX WTR COM 596680108 73,299 2,224 3.13 3,971 -12.82 0.0028
2025-05-15 2025-03-31 13F MIDDLESEX WTR COM 596680108 71,075 55,299 350.53 4,556 448.80 0.0041
2025-02-14 2024-12-31 13F MIDDLESEX WTR COM 596680108 15,776 9,013 133.27 830 88.21 0.0006
2024-11-14 2024-09-30 13F MIDDLESEX WTR COM 596680108 6,763 -30,240 -81.72 441 -77.19 0.0004
2024-08-14 2024-06-30 13F MIDDLESEX WTR COM 596680108 37,003 13,364 56.53 1,934 55.76 0.0018
2024-05-15 2024-03-31 13F MIDDLESEX WTR COM 596680108 23,639 23,639 1,241 0.0011
2023-08-14 2023-06-30 13F MIDDLESEX WTR COM 596680108 0 -6,122 -100.00 0 -100.00
2023-05-15 2023-03-31 13F MIDDLESEX WTR COM 596680108 6,122 -16,798 -73.29 478 -73.49 0.0005
2023-02-14 2022-12-31 13F MIDDLESEX WTR COM 596680108 22,920 4,064 21.55 1,803 23.83 0.0020
2022-11-14 2022-09-30 13F MIDDLESEX WTR COM 596680108 18,856 14,451 328.06 1,456 277.20 0.0017
2022-08-15 2022-06-30 13F MIDDLESEX WTR COM 596680108 4,405 4,405 386 0.0005
2021-08-16 2021-06-30 13F MIDDLESEX WTR COM 596680108 0 -9,919 -100.00 0 -100.00
2021-05-17 2021-03-31 13F MIDDLESEX WTR COM 596680108 9,919 9,919 784 0.0008
2018-08-14 2018-06-30 13F MIDDLESEX WATER COM 596680108 0 -7,843 -100.00 0 -100.00
2018-05-15 2018-03-31 13F MIDDLESEX WATER COM 596680108 7,843 7,843 288 0.0004
2016-05-16 2016-03-31 13F MIDDLESEX WATER COM 596680108 0 0 0 0.0000
2016-02-16 2015-12-31 13F MIDDLESEX WATER COM 596680108 0 -9,765 -100.00 0 -100.00
2015-11-16 2015-09-30 13F MIDDLESEX WATER COM 596680108 9,765 -150 -1.51 233 4.02 0.0003
2015-08-14 2015-06-30 13F MIDDLESEX WATER COM 596680108 9,915 -3,295 -24.94 224 -25.58 0.0003
2015-05-15 2015-03-31 13F MIDDLESEX WATER COM 596680108 13,210 13,210 301 0.0005
2014-11-14 2014-09-30 13F MIDDLESEX WATER COM 596680108 0 -10,130 -100.00 0 -100.00
2014-08-14 2014-06-30 13F MIDDLESEX WATER COM 596680108 10,130 -1,016 -9.12 215 -7.73 0.0003
2014-02-14 2013-12-31 13F MIDDLESEX WATER COM 596680108 11,146 11,146 233 0.0003
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.