Proto Labs, Inc.
AT ˙ WBAG ˙ US7437131094
64,80 € ↓ -1,15 (-1,74%)
2026-06-04
DEL PRIS
SecurityAT:PRLB / Proto Labs, Inc.
InstitutionMillennium Management Llc
ManagerIsrael Englander
Latest Disclosed Ownership25,829 shares
Latest Disclosed Value $ 1,472,770
Millennium Management Llc ownership in PRLB / Proto Labs, Inc.

On May 15, 2026 - Millennium Management Llc filed a 13F-HR form disclosing ownership of 25,829 shares of Proto Labs, Inc. (AT:PRLB) valued at $1,251,673 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 101,532 shares of Proto Labs, Inc.. This represents a change in shares of -74.56% during the quarter. The current value of the position is $1,673,719 USD.

Millennium Management Llc has a history of taking positions in derivatives of the underlying security (PRLB) in the form of stock options. The firm currently holds call options representing 0 of underlying shares valued at $0 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

AT:PRLB / Proto Labs, Inc. Historical Put/Call Ratio
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 25,829 -75,703 -74.56 1,473 -71.34 0.0006
2026-02-17 2025-12-31 13F PROTO LABS COM 743713109 101,532 -2,636 -2.53 5,137 -1.44 0.0022
2025-11-14 2025-09-30 13F PROTO LABS COM 743713109 104,168 -51,005 -32.87 5,212 -16.13 0.0022
2025-08-14 2025-06-30 13F PROTO LABS COM 743713109 155,173 155,173 6,213 0.0030
2025-05-15 2025-03-31 13F PROTO LABS COM 743713109 0 -31,011 -100.00 0 -100.00
2025-02-14 2024-12-31 13F PROTO LABS COM 743713109 31,011 -12,609 -28.91 1,212 -5.39 0.0006
2024-11-14 2024-09-30 13F PROTO LABS COM 743713109 43,620 -4,643 -9.62 1,281 -14.03 0.0006
2024-08-14 2024-06-30 13F PROTO LABS COM 743713109 48,263 -517 -1.06 1,491 -14.52 0.0007
2024-05-15 2024-03-31 13F PROTO LABS COM 743713109 48,780 -115,825 -70.37 1,744 -72.82 0.0007
2024-02-14 2023-12-31 13F PROTO LABS COM 743713109 164,605 15,012 10.04 6,413 62.40 0.0028
2023-11-14 2023-09-30 13F PROTO LABS COM 743713109 149,593 -66,534 -30.78 3,949 -47.73 0.0020
2023-08-14 2023-06-30 13F PROTO LABS COM 743713109 216,127 164,819 321.23 7,556 344.15 0.0037
2023-05-15 2023-03-31 13F PROTO LABS COM 743713109 51,308 -58,670 -53.35 1,701 -39.42 0.0010
2023-02-14 2022-12-31 13F PROTO LABS COM 743713109 109,978 64,892 143.93 2,808 71.01 0.0016
2022-11-14 2022-09-30 13F PROTO LABS COM 743713109 45,086 -88,584 -66.27 1,642 -74.32 0.0010
2022-08-15 2022-06-30 13F PROTO LABS COM 743713109 133,670 -80,230 -37.51 6,395 -43.48 0.0040
2022-05-16 2022-03-31 13F PROTO LABS COM 743713109 213,900 56,961 36.29 11,315 40.40 0.0060
2022-02-14 2021-12-31 13F PROTO LABS COM 743713109 156,939 32,847 26.47 8,059 -2.49 0.0041
2021-11-15 2021-09-30 13F PROTO LABS COM 743713109 124,092 84,697 214.99 8,265 128.57 0.0050
2021-08-16 2021-06-30 13F PROTO LABS COM 743713109 39,395 -58,624 -59.81 3,616 -69.70 0.0022
2021-05-17 2021-03-31 13F PROTO LABS COM 743713109 98,019 94,832 2,975.59 11,934 2,340.49 0.0085
2021-02-16 2020-12-31 13F PROTO LABS COM 743713109 3,187 -811 -20.29 489 -5.60 0.0004
2020-11-16 2020-09-30 13F PROTO LABS COM 743713109 3,998 -37,091 -90.27 518 -88.79 0.0006
2020-08-14 2020-06-30 13F PROTO LABS COM 743713109 41,089 -69,306 -62.78 4,621 -45.01 0.0063
2020-05-14 2020-03-31 13F PROTO LABS COM 743713109 110,395 -21,219 -16.12 8,404 -37.12 0.0189
2020-02-14 2019-12-31 13F PROTO LABS COM 743713109 131,614 84,853 181.46 13,365 179.95 0.0167
2019-11-14 2019-09-30 13F PROTO LABS COM 743713109 46,761 -14,669 -23.88 4,774 -33.02 0.0075
2019-08-15 2019-06-30 13F/A-1 PROTO LABS COM 743713109 61,430 37,498 156.69 7,127 183.27 0.0107
2019-05-14 2019-03-31 13F PROTO LABS COM 743713109 23,932 6,242 35.29 2,516 26.12 0.0038
2019-02-15 2018-12-31 13F/A-1 PROTO LABS COM 743713109 17,690 17,690 1,995 0.0031
2019-02-14 2018-12-31 13F PROTO LABS COM 743713109 17,690 1,995
2018-05-15 2018-03-31 13F PROTO LABS COM 743713109 0 -5,362 -100.00 0 -100.00
2018-02-14 2017-12-31 13F PROTO LABS COM 743713109 5,362 5,362 552 0.0008
2017-08-14 2017-06-30 13F PROTO LABS COM 743713109 0 -140,586 -100.00 0 -100.00
2017-05-15 2017-03-31 13F PROTO LABS COM 743713109 140,586 140,586 7,184 0.0132
2016-08-15 2016-06-30 13F PROTO LABS COM 743713109 0 -6,125 -100.00 0 -100.00
2016-05-16 2016-03-31 13F PROTO LABS COM 743713109 6,125 -4,605 -42.92 472 -30.89 0.0012
2016-02-16 2015-12-31 13F PROTO LABS COM 743713109 10,730 10,730 0.00 683 0.0014
2015-05-15 2015-03-31 13F PROTO LABS COM 743713109 0 -10,276 -100.00 0 -100.00
2015-02-17 2014-12-31 13F PROTO LABS COM 743713109 10,276 -60,352 -85.45 690 -86.27 0.0015
2014-02-14 2013-12-31 13F PROTO LABS COM 743713109 70,628 70,628 5,027 0.0159
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2019-11-14 2019-09-30 13F SURGERY PARTNERS COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2019-08-14 2019-06-30 13F SURGERY PARTNERS COM Call 100,000 814 n/a n/a n/a
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.