CarParts.com, Inc.
US ˙ NasdaqCM ˙ US14427M1071

SecurityPRTS / CarParts.com, Inc.
InstitutionRenaissance Technologies Llc
ManagerJames Simons
Latest Disclosed Ownership1,336,300 shares
Latest Disclosed Value $ 1,050,065
Renaissance Technologies Llc reports 1.21% decrease in ownership of PRTS / CarParts.com, Inc.

On May 14, 2026 - Renaissance Technologies Llc filed a 13F-HR form disclosing ownership of 1,336,300 shares of CarParts.com, Inc. (US:PRTS) valued at $1,050,065 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 1,352,700 shares of CarParts.com, Inc.. This represents a change in shares of -1.21% during the quarter. The current value of the position is $7,991,074 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 CARPARTS COM COM 14427M107 1,336,300 -16,400 -1.21 1,050 55.33 0.0016
2026-02-12 2025-12-31 13F CARPARTS COM COM 14427M107 1,352,700 35,900 2.73 676 -27.78 0.0010
2025-11-13 2025-09-30 13F CARPARTS COM COM 14427M107 1,316,800 124,800 10.47 936 6.12 0.0012
2025-08-13 2025-06-30 13F CARPARTS COM COM 14427M107 1,192,000 81,300 7.32 882 -20.54 0.0012
2025-05-14 2025-03-31 13F CARPARTS COM COM 14427M107 1,110,700 59,800 5.69 1,111 -2.12 0.0017
2025-02-13 2024-12-31 13F CARPARTS COM COM 14427M107 1,050,900 -540,400 -33.96 1,135 -21.36 0.0017
2024-11-13 2024-09-30 13F CARPARTS COM COM 14427M107 1,591,300 392,800 32.77 1,442 20.37 0.0022
2024-08-09 2024-06-30 13F CARPARTS COM COM 14427M107 1,198,500 232,500 24.07 1,198 119,700.00 0.0020
2024-05-13 2024-03-31 13F CARPARTS COM COM 14427M107 966,000 89,400 10.20 2 -50.00 0.0025
2024-02-13 2023-12-31 13F CARPARTS COM COM 14427M107 876,600 206,500 30.82 3 0.00 0.0043
2023-11-14 2023-09-30 13F CARPARTS COM COM 14427M107 670,100 229,291 52.02 3 100.00 0.0047
2023-08-11 2023-06-30 13F CARPARTS COM COM 14427M107 440,809 88,870 25.25 2 0.00 0.0027
2023-05-12 2023-03-31 13F CARPARTS COM COM 14427M107 351,939 -48,472 -12.11 2 -50.00 0.0025
2023-02-13 2022-12-31 13F CARPARTS COM COM 14427M107 400,411 -253,889 -38.80 3 -99.94 0.0034
2022-11-14 2022-09-30 13F CARPARTS COM COM 14427M107 654,300 -149,300 -18.58 3,383 -39.34 0.0048
2022-08-12 2022-06-30 13F CARPARTS COM COM 14427M107 803,600 -71,100 -8.13 5,577 -4.83 0.0066
2022-05-13 2022-03-31 13F CARPARTS COM COM 14427M107 874,700 639,100 271.26 5,860 122.05 0.0069
2022-02-11 2021-12-31 13F CARPARTS COM COM 14427M107 235,600 112,700 91.70 2,639 37.59 0.0033
2021-11-12 2021-09-30 13F CARPARTS COM COM 14427M107 122,900 122,900 1,918 0.0025
2021-08-13 2021-06-30 13F CARPARTS COM COM 14427M107 0 -403,603 -100.00 0 -100.00
2021-05-13 2021-03-31 13F CARPARTS COM COM 14427M107 403,603 -1,712,028 -80.92 5,763 -78.01 0.0072
2021-02-10 2020-12-31 13F CARPARTS COM COM 14427M107 2,115,631 -1,398,124 -39.79 26,213 -30.99 0.0285
2020-11-13 2020-09-30 13F CARPARTS COM COM 14427M107 3,513,755 3,513,755 37,984 0.0379
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.