Arkolith/Funds/Penbrook Management LLC

Penbrook Management LLC

CIK 1381055
Holdings as of Jun 30, 2026·disclosed Jul 23, 2026·~23-day 13F lag·13F-HR
Active Filer

Penbrook Management LLC holds a focused book of 101 stocks worth $156.8M as of Q2 2026 (disclosed Jul 23, 2026, a ~45-day 13F lag). This quarter they opened Seabridge Gold Inc and trimmed Microsoft Corp. Their largest long position is Novo-Nordisk A/s-Spons ADR at 10% of the equity book. Cloning the disclosed picks since 2025 would be +26% (+16.7%/yr). That is a simulation of the disclosed long book, not audited returns.

Build

Build on this 13F portfolio

The public view is the crawlable proof. The same sourced dataset is available through REST and MCP for agents, research scripts, and back-office tools.

Build

Ask your agent what Penbrook Management LLC owns

This fund page is the Follow view. The Build view lets your agent pull holdings, quarter changes, overlap, and source filings through API or MCP.

Copy-paste
curl -H "Authorization: Bearer YOUR_API_KEY" \
  "https://arkolith.com/api/v1/funds/1381055/holdings"
Ask your agent
Use Arkolith to show Penbrook Management LLC's latest
holdings, largest changes, and filing provenance.
Opened
49
new positions
Added to
17
existing
Trimmed
22
reduced
Sold out
5
exited

Growth of $10,000: cloning the disclosed book

If you'd copied them
+26.2%
+16.7%/yr · since Jan '25
Their reported book
+18.5%
held from quarter-end
S&P 500
+22.9%
same window
$8K$9K$11K$12K$13KJan '25May '25Aug '25Dec '25Apr '26Jul '26
Penbrook Management LLC (copied at disclosure) S&P 500

Following at the filing date actually beat the quarter-end book by 7.6 points over this window.

Growth of $10,000 cloning Penbrook Management LLC's disclosed long 13F book, rebalanced on each filing date (so it reflects the ~45-day reporting lag, no look-ahead), total-return basis (dividends reinvested), derived from end-of-day prices. “Their reported book” values the same picks from quarter-end, before they were public. S&P 500 is SPY total return over the same window. Excludes shorts, cash, options and non-13F holdings. Not investment advice.

Concentration

Top-heavy: focused book

Top 5 holdings
33%
Top 10 holdings
45%
Top 20 holdings
61%

Share of the disclosed book in its largest positions. A higher top-5 share means a more concentrated, higher-conviction portfolio.

Direct sector allocation

94% mapped to company sectors

Information Technology
39%
Health Care
19%
Consumer Discretionary
8%
Financials
8%
ETF / fund or unclassified
6%
Communication Services
5%
Utilities
5%
Energy
5%

Direct operating-company sectors from our SIC-based security master. ETF/fund and unclassified holdings stay visible separately; this is not ETF look-through exposure.

Biggest moves: latest quarter

Estimated $ traded · quarter-end prices, no cost basis

Bought
Trimmed / exited

Holdings: largest first

Bars show each stock's share of the portfolio. Click a row for its position history.

101 positions
#SecurityValueShares% PortLast moveHistory
1Novo-Nordisk A S ADR
ADR
$15.2M316.2K
9.7%
Held
2Amazon Com Inc
Stock
$12.3M51.8K
7.9%
Held
3Alphabet Inc Cap STK CL A
Stock
$8.3M23.2K
5.3%
Held
4Microsoft Corp
Stock
$8.2M21.9K
5.2%
−1.5%
Reduced · −325 sh
5Alphabet Inc Cap STK CL C
Stock
$8.0M22.6K
5.1%
Held
6Moodys Corp
Stock
$6.2M13.6K
3.9%
Held
7Electrovaya Inc
Stock
$3.4M326.2K
2.2%
+10%
Added · +31K sh
8Cryoport Inc Com Par $0.001
Stock
$3.2M202.7K
2.0%
+9.1%
Added · +17K sh
9Viemed Healthcare Inc
Stock
$3.2M277.2K
2.0%
+1.8%
Added · +5K sh
10Marvell Technology Inc
Stock
$2.9M9.7K
1.8%
Held
11Photronics Inc
Stock
$2.9M89.1K
1.8%
−7.9%
Reduced · −8K sh
12Seabridge Gold Inc
Stock
$2.9M110.9K
1.8%
New
New position
13Extreme Networks Inc
Stock
$2.7M84.0K
1.7%
+0.6%
Added · +500 sh
14Planet Labs PBC Com CL A
Stock
$2.7M81.8K
1.7%
−23%
Reduced · −24K sh
15Prothena Corp PLC SHS
Stock
$2.7M271.7K
1.7%
Held
16Alkami Technology Inc
Stock
$2.5M140.6K
1.6%
+10%
Added · +13K sh
17Allot Ltd SHS
Stock
$2.4M275.3K
1.6%
New
New position
18Cisco Sys Inc
Stock
$2.2M18.4K
1.4%
Held
19Blackstone Inc
Stock
$2.1M18.1K
1.4%
Held
20Magnite Inc
Stock
$2.1M112.0K
1.4%
−0.1%
Reduced · −150 sh
21Axcelis Technologies Inc
Stock
$2.1M10.9K
1.3%
−9.9%
Reduced · −1K sh
22Curiositystream Inc Com CL A
Stock
$2.0M764.8K
1.3%
+13%
Added · +90K sh
23Thomson Reuters Corp
Stock
$2.0M24.4K
1.3%
New
New position
24Nuveen N Y Mun Value FD
CEF
$1.9M213.7K
1.2%
Held
25Vermilion Energy Inc
Stock
$1.9M197.8K
1.2%
Held
26Targa Res Corp
Stock
$1.8M6.9K
1.2%
Held
27Berkshire Hathaway Inc Del CL B New
Stock
$1.6M3.3K
1.1%
−0.3%
Reduced · −10 sh
28Baytex Energy Corp
Stock
$1.6M399.4K
1.0%
New
New position
29Energy Transfer L P Com Ut Ltd PTN
Stock
$1.4M74.5K
0.9%
Held
30Williams Cos Inc
Stock
$1.4M19.1K
0.9%
Held
31Automatic Data Processing Inc
Stock
$1.4M6.3K
0.9%
Held
32Data I O Corp
Stock
$1.4M355.9K
0.9%
−0.3%
Reduced · −1K sh
33Sony Group Corp Sponsored ADR
ADR
$1.4M68.5K
0.9%
Held
34Abbvie Inc
Stock
$1.3M5.2K
0.8%
−0.3%
Reduced · −18 sh
35Verizon Communications Inc
Stock
$1.3M30.4K
0.8%
+1.8%
Added · +525 sh
36Airbnb Inc Com CL A
Stock
$1.3M8.9K
0.8%
Held
37State Street SPDR S&P 500 ETF
ETF
$1.2M1.6K
0.8%
Held
38Mesoblast Ltd Spons ADR
ADR
$1.2M87.1K
0.8%
Held
39Hess Midstream LP CL A SHS
Stock
$1.1M30.1K
0.7%
Held
40Biolife Solutions Inc
Stock
$1.1M39.7K
0.7%
+71%
Added · +17K sh
41Doubleverify Hldgs Inc
Stock
$1.1M102.7K
0.7%
−0.2%
Reduced · −250 sh
42USA Compression Partners LP Com Unit Ltdpar
Stock
$1.1M41.0K
0.7%
Held
43NPK International Inc Com SHS
Stock
$1.1M67.8K
0.7%
+0.8%
Added · +575 sh
44Nvidia Corporation
Stock
$1.1M5.3K
0.7%
+1.9%
Added · +100 sh
45Oneok Inc
Stock
$983K11.3K
0.6%
Held
46Meta Platforms Inc CL A
Stock
$958K1.7K
0.6%
Held
47Kulicke & Soffa Inds Inc
Stock
$950K7.1K
0.6%
Held
48Par Technology Corp
Stock
$936K53.8K
0.6%
+50%
Added · +18K sh
49Popular Inc Com New
Stock
$870K5.3K
0.6%
−3.6%
Reduced · −200 sh
50Novartis AG Sponsored ADR
ADR
$868K5.5K
0.6%
Held
Showing 50 of 101 positions

Filing history

As-of date vs the date the SEC received each filing

QuarterAs ofFiledPositionsValueForm
Q2 2026Jun 30, 2026Jul 23, 2026101$156.8M13F-HR
Q1 2026Mar 31, 2026Apr 21, 202693$132.1M13F-HR
Q4 2025Dec 31, 2025Jan 6, 202697$145.0M13F-HR
Q3 2025Sep 30, 2025Oct 22, 2025104$143.2M13F-HR
Q2 2025Jun 30, 2025Jul 28, 2025102$133.0M13F-HR/A
Q1 2025Mar 31, 2025Apr 1, 2025107$132.3M13F-HR
Q4 2024Dec 31, 2024Jan 23, 2025110$146.6M13F-HR
Amended / restated
  • Q2 2025 · filed Jul 25, 202513F-HR · superseded

Data source

Holdings from SEC EDGAR 13F-HR filings, updated quarterly ~45 days after quarter-end. Public domain. The book and weighting are long equity only; disclosed put/call options are listed separately and excluded from those totals. The performance line is a simulation of the disclosed long book, not an audited return.