Proto Labs, Inc.
US ˙ NYSE ˙ US7437131094

SecurityPRLB / Proto Labs, Inc.
InstitutionBridgeway Capital Management Inc
Latest Disclosed Ownership22,000 shares
Latest Disclosed Value $ 1,254,440
Bridgeway Capital Management Inc reports 80.68% decrease in ownership of PRLB / Proto Labs, Inc.

On May 15, 2026 - Bridgeway Capital Management Inc filed a 13F-HR form disclosing ownership of 22,000 shares of Proto Labs, Inc. (US:PRLB) valued at $1,254,440 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 113,876 shares of Proto Labs, Inc.. This represents a change in shares of -80.68% during the quarter. The current value of the position is $1,642,740 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 PROTO LABS COM 743713109 22,000 -91,876 -80.68 1,254 -78.23 0.0252
2026-02-17 2025-12-31 13F PROTO LABS COM 743713109 113,876 4,335 3.96 5,761 5.11 0.1207
2025-11-14 2025-09-30 13F PROTO LABS COM 743713109 109,541 5,274 5.06 5,480 31.29 0.1169
2025-08-14 2025-06-30 13F PROTO LABS COM 743713109 104,267 4,873 4.90 4,175 19.87 0.0991
2025-05-15 2025-03-31 13F PROTO LABS COM 743713109 99,394 3,035 3.15 3,483 -7.54 0.0877
2025-02-14 2024-12-31 13F PROTO LABS COM 743713109 96,359 43,358 81.81 3,767 142.03 0.0843
2024-11-14 2024-09-30 13F PROTO LABS COM 743713109 53,001 -45,456 -46.17 1,557 -48.83 0.0337
2024-08-14 2024-06-30 13F PROTO LABS COM 743713109 98,457 -35,794 -26.66 3,041 -36.63 0.0712
2024-05-15 2024-03-31 13F PROTO LABS COM 743713109 134,251 5,950 4.64 4,799 -3.98 0.0981
2024-02-14 2023-12-31 13F PROTO LABS COM 743713109 128,301 6,528 5.36 4,999 55.51 0.1072
2023-11-14 2023-09-30 13F PROTO LABS COM 743713109 121,773 30,246 33.05 3,215 0.47 0.0779
2023-08-14 2023-06-30 13F PROTO LABS COM 743713109 91,527 26,040 39.76 3,200 47.42 0.0766
2023-05-15 2023-03-31 13F PROTO LABS COM 743713109 65,487 37,687 135.56 2,171 206.06 0.0576
2023-02-14 2022-12-31 13F PROTO LABS COM 743713109 27,800 27,800 710 0.0184
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.