Automatic Data Processing, Inc.
US ˙ NasdaqGS ˙ US0530151036

SecurityADP / Automatic Data Processing, Inc.
InstitutionMairs & Power Inc
Latest Disclosed Ownership124,436 shares
Latest Disclosed Value $ 25,282,906
Mairs & Power Inc reports 12.33% increase in ownership of ADP / Automatic Data Processing, Inc.

On May 13, 2026 - Mairs & Power Inc filed a 13F-HR form disclosing ownership of 124,436 shares of Automatic Data Processing, Inc. (US:ADP) valued at $25,282,906 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 110,781 shares of Automatic Data Processing, Inc.. This represents a change in shares of 12.33% during the quarter. The current value of the position is $28,340,299 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)
2026-05-13 2026-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 124,436 13,655 12.33 25,283 -11.28 0.2584
2026-02-17 2025-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 110,781 5,674 5.40 28,496 -7.62 0.2743
2025-11-14 2025-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 105,107 3,724 3.67 30,849 -1.34 0.2899
2025-08-14 2025-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 101,383 -6,777 -6.27 31,267 -5.39 0.3086
2025-05-15 2025-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 108,160 -254 -0.23 33,046 4.13 0.3438
2025-02-14 2024-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 108,414 -116 -0.11 31,736 5.67 0.3070
2024-11-14 2024-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 108,530 1,914 1.80 30,034 18.02 0.2825
2024-08-14 2024-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 106,616 10,425 10.84 25,448 5.94 0.2459
2024-05-15 2024-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 96,191 9,960 11.55 24,023 19.58 0.2326
2024-02-14 2023-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 86,231 2,670 3.20 20,089 -0.07 0.2117
2023-11-14 2023-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 83,561 14,875 21.66 20,103 33.17 0.2359
2023-08-14 2023-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 68,686 38,825 130.02 15,096 127.11 0.1642
2023-05-15 2023-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 29,861 93 0.31 6,648 -6.51 0.0767
2023-02-14 2022-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 29,768 -244 -0.81 7,110 4.74 0.0856
2022-11-14 2022-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 30,012 -2,748 -8.39 6,788 -1.35 0.0856
2022-08-15 2022-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 32,760 -262 -0.79 6,881 -8.42 0.0825
2022-05-16 2022-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 33,022 13,945 73.10 7,514 59.74 0.0757
2022-02-14 2021-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 19,077 200 1.06 4,704 24.64 0.0436
2021-11-15 2021-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 18,877 0 0.00 3,774 0.67 0.0378
2021-08-16 2021-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 18,877 12,550 198.36 3,749 214.51 0.0371
2021-05-14 2021-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 6,327 1,700 36.74 1,192 46.26 0.0125
2021-02-16 2020-12-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 4,627 -137 -2.88 815 22.56 0.0091
2020-11-16 2020-09-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 4,764 -408 -7.89 665 -13.64 0.0083
2020-08-14 2020-06-30 13F AUTOMATIC DATA PROCESSING IN COM 053015103 5,172 0 0.00 770 8.91 0.0101
2020-05-15 2020-03-31 13F AUTOMATIC DATA PROCESSING IN COM 053015103 5,172 0 0.00 707 -19.84 0.0103
2020-02-14 2019-12-31 13F Automatic Data Proc COM 053015103 5,172 120 2.38 882 8.22 0.0100
2019-11-14 2019-09-30 13F Automatic Data Proc COM 053015103 5,052 0 0.00 815 -2.40 0.0099
2019-08-14 2019-06-30 13F Automatic Data Proc COM 053015103 5,052 0 0.00 835 3.47 0.0100
2019-05-15 2019-03-31 13F Automatic Data Proc COM 053015103 5,052 0 0.00 807 21.90 0.0098
2019-02-14 2018-12-31 13F Automatic Data Proc COM 053015103 5,052 0 0.00 662 -13.01 0.0089
2018-11-14 2018-09-30 13F Automatic Data Proc COM 053015103 5,052 0 0.00 761 12.24 0.0089
2018-08-14 2018-06-30 13F Automatic Data Proc COM 053015103 5,052 0 0.00 678 18.32 0.0084
2018-05-15 2018-03-31 13F Automatic Data Proc COM 053015103 5,052 -1,715 -25.34 573 -27.74 0.0071
2018-02-14 2017-12-31 13F Automatic Data Proc COM 053015103 6,767 0 0.00 793 7.16 0.0092
2017-11-14 2017-09-30 13F Automatic Data Proc COM 053015103 6,767 950 16.33 740 24.16 0.0089
2017-08-14 2017-06-30 13F Automatic Data Proc COM 053015103 5,817 892 18.11 596 18.25 0.0072
2017-05-15 2017-03-31 13F Automatic Data Proc COM 053015103 4,925 423 9.40 504 8.86 0.0062
2017-02-14 2016-12-31 13F Automatic Data Proc COM 053015103 4,502 -900 -16.66 463 -2.73 0.0059
2016-11-14 2016-09-30 13F Automatic Data Proc COM 053015103 5,402 900 19.99 476 14.98 0.0063
2016-08-15 2016-06-30 13F Automatic Data Proc COM 053015103 4,502 0 0.00 414 2.48 0.0056
2016-05-16 2016-03-31 13F Automatic Data Proc COM 053015103 4,502 0 0.00 404 6.04 0.0057
2016-02-16 2015-12-31 13F Automatic Data Proc COM 053015103 4,502 -275 -5.76 381 -0.78 0.0057
2015-11-16 2015-09-30 13F Automatic Data Proc COM 053015103 4,777 -100 -2.05 384 -1.79 0.0060
2015-08-14 2015-06-30 13F Automatic Data Proc COM 053015103 4,877 -75 -1.51 391 -7.78 0.0055
2015-05-15 2015-03-31 13F Automatic Data Proc COM 053015103 4,952 0 0.00 424 2.66 0.0058
2015-02-17 2014-12-31 13F Automatic Data Proc COM 053015103 4,952 -250 -4.81 413 -4.40 0.0057
2014-11-14 2014-09-30 13F Automatic Data Proc COM 053015103 5,202 0 0.00 432 4.85 0.0063
2014-08-14 2014-06-30 13F Automatic Data Proc COM 053015103 5,202 0 0.00 412 2.49 0.0058
2014-05-15 2014-03-31 13F Automatic Data Proc COM 053015103 5,202 -127 -2.38 402 -6.73 0.0060
2014-02-14 2013-12-31 13F Automatic Data Proc COM 053015103 5,329 202 3.94 431 16.17 0.0066
2013-11-14 2013-09-30 13F Automatic Data Proc COM 053015103 5,127 127 2.54 371 7.85 0.0064
2013-08-14 2013-06-30 13F Automatic Data Proc COM 053015103 5,000 5,000 344 0.0066
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.