Advanced Drainage Systems, Inc.
MX ˙ BMV ˙ US00790R1041
SecurityMX:WMS / Advanced Drainage Systems, Inc.
InstitutionBeck Mack & Oliver Llc
Latest Disclosed Ownership11,662 shares
Latest Disclosed Value $ 1,599,210
Beck Mack & Oliver Llc reports 11.67% increase in ownership of WMS / Advanced Drainage Systems, Inc.

On May 12, 2026 - Beck Mack & Oliver Llc filed a 13F-HR form disclosing ownership of 11,662 shares of Advanced Drainage Systems, Inc. (MX:WMS) valued at $1,599,210 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 10,443 shares of Advanced Drainage Systems, Inc.. This represents a change in shares of 11.67% 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)
2026-05-12 2026-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 11,662 1,219 11.67 1,599 5.75 0.0330
2026-02-12 2025-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 10,443 -251 -2.35 1,512 1.96 0.0275
2025-11-14 2025-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 10,694 -1,500 -12.30 1,483 5.93 0.0270
2025-08-14 2025-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 12,194 -1,871 -13.30 1,401 -8.38 0.0267
2025-05-15 2025-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 14,065 -8,192 -36.81 1,528 -40.59 0.0305
2025-02-13 2024-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 22,257 -13,784 -38.25 2,573 -54.59 0.0476
2024-11-13 2024-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 36,041 -4,460 -11.01 5,664 -12.79 0.1102
2024-08-14 2024-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 40,501 3,237 8.69 6,496 1.20 0.1346
2024-05-14 2024-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 37,264 -384 -1.02 6,418 21.23 0.1301
2024-02-14 2023-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 37,648 -59,631 -61.30 5,295 -52.19 0.1232
2023-11-14 2023-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 97,279 -27,858 -22.26 11,073 -22.23 0.2898
2023-08-08 2023-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 125,137 -80,720 -39.21 14,238 -17.87 0.3720
2023-05-15 2023-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 205,857 -43,479 -17.44 17,335 -15.18 0.5008
2023-02-14 2022-12-31 13F/A-1 ADVANCED DRAIN SYS INC COM COM 00790R104 249,336 -22,431 -8.25 20,438 -39.53 0.6000
2023-02-14 2022-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 249,336 -22,431 20,438 0.5772
2022-11-10 2022-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 271,767 -54,138 -16.61 33,800 15.15 1.0914
2022-08-12 2022-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 325,905 -56,874 -14.86 29,354 -35.45 0.8803
2022-05-16 2022-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 382,779 -242,389 -38.77 45,478 -46.56 1.1391
2022-01-28 2021-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 625,168 -18,552 -2.88 85,104 22.22 2.0262
2021-11-04 2021-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 643,720 -9,320 -1.43 69,631 -8.53 1.8067
2021-07-28 2021-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 653,040 12,502 1.95 76,125 14.95 2.0254
2021-05-11 2021-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 640,538 -355,970 -35.72 66,225 -20.49 2.0452
2021-02-10 2020-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 996,508 -54,303 -5.17 83,288 26.94 2.7650
2020-11-02 2020-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 1,050,811 -27,359 -2.54 65,613 23.19 2.4104
2020-08-10 2020-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 1,078,170 16,184 1.52 53,262 70.36 1.9798
2020-05-05 2020-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 1,061,986 98,709 10.25 31,265 -16.44 1.3904
2020-02-07 2019-12-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 963,277 -665 -0.07 37,414 20.28 1.2362
2019-11-06 2019-09-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 963,942 218,000 29.22 31,106 27.18 1.0956
2019-08-13 2019-06-30 13F ADVANCED DRAIN SYS INC COM COM 00790R104 745,942 15,517 2.12 24,459 29.94 0.8595
2019-05-02 2019-03-31 13F ADVANCED DRAIN SYS INC COM COM 00790R104 730,425 730,425 18,823 0.6732
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.