Dorman Products, Inc.
US ˙ NasdaqGS ˙ US2582781009

SecurityDORM / Dorman Products, Inc.
InstitutionJanus Henderson Group Plc
Latest Disclosed Ownership11,754 shares
Latest Disclosed Value $ 1,227,353
Janus Henderson Group Plc ownership in DORM / Dorman Products, Inc.

On May 18, 2026 - Janus Henderson Group Plc filed a 13F-HR/A form disclosing ownership of 11,754 shares of Dorman Products, Inc. (US:DORM) valued at $1,226,647 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 11,754 shares of Dorman Products, Inc.. This represents a change in shares of 0.00% during the quarter. The current value of the position is $1,504,982 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)
2026-05-18 2026-03-31 13F/A-1 DORMAN PRODS COM 258278100 11,754 0 0.00 1,227 -15.32 0.0002
2026-05-15 2026-03-31 13F DORMAN PRODS COM 258278100 11,754 0 0.00 1,227 -15.32 0.0002
2026-02-17 2025-12-31 13F DORMAN PRODS COM 258278100 11,754 0 0.00 1,449 -20.91 0.0006
2025-11-14 2025-09-30 13F DORMAN PRODS COM 258278100 11,754 0 0.00 1,833 27.13 0.0008
2025-08-14 2025-06-30 13F DORMAN PRODS COM 258278100 11,754 -7,744 -39.72 1,442 -38.73 0.0007
2025-05-15 2025-03-31 13F DORMAN PRODS COM 258278100 19,498 7,744 65.88 2,353 54.33 0.0013
2025-02-14 2024-12-31 13F DORMAN PRODS COM 258278100 11,754 -71,791 -85.93 1,524 -83.87 0.0008
2024-11-14 2024-09-30 13F DORMAN PRODS COM 258278100 83,545 -128,169 -60.54 9,450 -51.20 0.0048
2024-08-14 2024-06-30 13F DORMAN PRODS COM 258278100 211,714 -13,275 -5.90 19,367 -10.69 0.0104
2024-05-15 2024-03-31 13F DORMAN PRODS COM 258278100 224,989 -1,232 -0.54 21,686 14.93 0.0118
2024-02-14 2023-12-31 13F DORMAN PRODS COM 258278100 226,221 -581 -0.26 18,868 9.81 0.0113
2023-11-14 2023-09-30 13F DORMAN PRODS COM 258278100 226,802 -8,915 -3.78 17,182 -7.52 0.0113
2023-08-14 2023-06-30 13F DORMAN PRODS COM 258278100 235,717 -51,823 -18.02 18,581 -25.09 0.0116
2023-05-15 2023-03-31 13F DORMAN PRODS COM 258278100 287,540 37,732 15.10 24,803 22.78 0.0164
2023-02-14 2022-12-31 13F DORMAN PRODS COM 258278100 249,808 245,159 5,273.37 20,202 5,188.22 0.0144
2022-11-14 2022-09-30 13F DORMAN PRODS COM 258278100 4,649 -19 -0.41 382 -25.54 0.0003
2022-08-15 2022-06-30 13F DORMAN PRODS COM 258278100 4,668 -1,199 -20.44 513 -7.90 0.0004
2022-05-16 2022-03-31 13F DORMAN PRODS COM 258278100 5,867 1 0.02 557 -15.99 0.0003
2022-02-14 2021-12-31 13F DORMAN PRODS COM 258278100 5,866 2,947 100.96 663 140.22 0.0003
2021-11-16 2021-09-30 13F DORMAN PRODS COM 258278100 2,919 2,919 276 0.0001
2020-08-14 2020-06-30 13F DORMAN PRODUCTS COM 258278100 0 -525,119 -100.00 0 -100.00
2020-05-14 2020-03-31 13F DORMAN PRODUCTS COM 258278100 525,119 -549,110 -51.12 29,023 -64.32 0.0200
2020-02-18 2019-12-31 13F DORMAN PRODUCTS COM 258278100 1,074,229 98,297 10.07 81,341 4.79 0.0416
2019-11-14 2019-09-30 13F DORMAN PRODUCTS COM 258278100 975,932 309,224 46.38 77,626 33.61 0.0420
2019-07-31 2019-06-30 13F DORMAN PRODUCTS COM 258278100 666,708 -76,076 -10.24 58,097 -11.21 0.0316
2019-04-30 2019-03-31 13F DORMAN PRODUCTS COM 258278100 742,784 -39,667 -5.07 65,432 -7.10 0.0363
2019-02-06 2018-12-31 13F DORMAN PRODUCTS COM 258278100 782,451 -9,321 -1.18 70,436 15.65 0.0449
2018-11-09 2018-09-30 13F DORMAN PRODUCTS COM 258278100 791,772 -4,807 -0.60 60,903 11.93 0.0325
2018-08-10 2018-06-30 13F DORMAN PRODUCTS COM 258278100 796,579 110,326 16.08 54,414 19.76 0.0310
2018-05-14 2018-03-31 13F DORMAN PRODUCTS COM 258278100 686,253 311,027 82.89 45,437 98.06 0.0268
2018-03-12 2017-12-31 13F/A-1 DORMAN PRODUCTS COM 258278100 375,226 139,452 59.15 22,941 35.86 0.0141
2018-02-09 2017-12-31 13F DORMAN PRODUCTS COM 258278100 375,226 139,452 22,941
2017-11-14 2017-09-30 13F DORMAN PRODUCTS COM 258278100 235,774 -71,300 -23.22 16,886 -33.56 0.0108
2017-08-17 2017-06-30 13F/A-1 DORMAN PRODUCTS COM 258278100 307,074 -14,755 -4.58 25,417 -3.84 0.0173
2017-08-14 2017-06-30 13F DORMAN PRODUCTS COM 258278100 307,074 -14,755 25,417
2017-05-03 2017-03-31 13F DORMAN PRODUCTS COM 258278100 321,829 -14,637 -4.35 26,432 7.53 0.1856
2017-01-30 2016-12-31 13F DORMAN PRODUCTS COM 258278100 336,466 638 0.19 24,582 14.55 0.1813
2016-10-24 2016-09-30 13F DORMAN PRODUCTS COM 258278100 335,828 -2,244 -0.66 21,459 10.97 0.1581
2016-07-29 2016-06-30 13F DORMAN PRODUCTS COM 258278100 338,072 123,617 57.64 19,338 65.69 0.1608
2016-05-12 2016-03-31 13F DORMAN PRODUCTS COM 258278100 214,455 -6,221 -2.82 11,671 11.42 0.0947
2016-02-03 2015-12-31 13F DORMAN PRODUCTS COM 258278100 220,676 3,508 1.62 10,475 -5.22 0.0841
2015-11-16 2015-09-30 13F DORMAN PRODUCTS COM 258278100 217,168 6,401 3.04 11,052 10.02 0.0974
2015-08-17 2015-06-30 13F DORMAN PRODUCTS COM 258278100 210,767 67,167 46.77 10,045 5.83 0.0789
2015-06-02 2015-03-31 13F/A-1 DORMAN PRODUCTS COM 258278100 143,600 143,600 9,492 0.0732
2015-05-15 2015-03-31 13F DORMAN PRODUCTS COM 258278100 143,600 9,492
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.