Arkolith/Funds/Nierenberg Investment Management Company, LLC

Nierenberg Investment Management Company, LLC

CIK 1282683
Holdings as of Jun 30, 2026·disclosed Aug 11, 2026·~42-day 13F lag·13F-HR
Active Filer

Nierenberg Investment Management Company, LLC holds a concentrated book of 35 stocks worth $201.4M as of Q2 2026 (disclosed Aug 11, 2026, a ~42-day 13F lag). This quarter they opened Haemonetics Corp/mass and trimmed Ishares 0-3 Month Treasury B. Their largest long position is Ishares 0-3 Month Treasury B at 23% of the equity book. Cloning the disclosed picks since 2024 would be +0% (+0.0%/yr). That is a simulation of the disclosed long book, not audited returns.

Opened
35
bought for the first time
Added to
2
already held, bought more
Trimmed
2
sold some, still holds it
Sold out
12
exited the position entirely

Growth of $10,000: cloning the disclosed book

If you'd copied them
+0.1%
+0.0%/yr · since Nov '24
Their reported book
+12.6%
held from quarter-end
S&P 500
+31.8%
same window
$9K$10K$11K$12K$13KNov '24Mar '25Jul '25Dec '25Apr '26Aug '26
Nierenberg Investment Management Company, LLC (copied at disclosure) S&P 500

The reported book (valued from quarter-end) returned +12.6%, a 12.5-point gap that is the cost of the ~42-day 13F disclosure lag a real follower can't avoid.

Growth of $10,000 cloning Nierenberg Investment Management Company, LLC's disclosed long 13F book, rebalanced on each filing date (so it reflects each quarter's actual reporting lag, ~42 days for the latest filing, with 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: concentrated book

Top 5 holdings
63%
Top 10 holdings
86%
Top 20 holdings
97%

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

Direct sector allocation

77% mapped to company sectors

Industrials
40%
ETF / fund or unclassified
23%
Energy
16%
Financials
12%
Health Care
4%
Real Estate
2%
Information Technology
2%
Consumer Discretionary
0%

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

Funds with the most overlap

Other tracked managers holding the same core names as Nierenberg Investment Management Company, LLC

Manager / fundShared namesTheir $ in those
BlackRock, Inc.68 / 35$37.2B
MORGAN STANLEY68 / 35$8.9B
UBS Group AG68 / 35$4.2B
GEODE CAPITAL MANAGEMENT, LLC67 / 35$10.2B
GOLDMAN SACHS GROUP INC67 / 35$3.8B
NORTHERN TRUST CORP67 / 35$3.5B
SUSQUEHANNA INTERNATIONAL GROUP, LLP67 / 35$559.1M
VANGUARD CAPITAL MANAGEMENT LLC66 / 35$22.5B

Ranked by how many of Nierenberg Investment Management Company, LLC's top 35 disclosed names each fund also holds: a cross-fund conviction signal from the latest 13F of every tracked manager.

Holdings: largest first

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

35 positions
#SecurityValueShares% PortLast moveHistory
1Ishares TR
0-3 MTH TREASURY
$46.4M461.0K
23.0%
−16%
Reduced · −90K sh
2Eqt Corp
COM
$28.4M533.4K
14.1%
Held
3Criteo S A
SPONS ADS
$19.2M1.05M
9.6%
Held
4Lyft Inc
CL A COM
$18.9M1.30M
9.4%
Held
5Maplebear Inc
COM
$13.8M291.9K
6.9%
Held
6KBR Inc
COM
$13.3M386.4K
6.6%
Held
7Riverview Bancorp Inc
COM
$11.0M2.03M
5.5%
Held
8Fti Consulting Inc
COM
$11.0M73.9K
5.5%
+655%
Added · +64K sh
9Rocket Cos Inc
COM CL A
$6.8M429.6K
3.4%
Held
10Green Dot Corp
CL A
$4.6M339.1K
2.3%
Held
11Diversified Healthcare TR
COM SH BEN INT
$4.2M456.1K
2.1%
Held
12Brookdale SR Living Inc
COM
$4.1M255.1K
2.0%
Held
13Five9 Inc
COM
$2.9M135.8K
1.4%
Held
14Tandem Diabetes Care Inc
COM NEW
$2.4M158.9K
1.2%
+100%
Added · +79K sh
15Haemonetics Corp Mass
COM
$2.0M26.3K
1.0%
New
New position
16Greenlight Cap Re Ltd
CLASS A
$1.7M102.5K
0.8%
Held
17Ring Energy Inc
COM
$1.5M1.40M
0.8%
New
New position
18Concentrix Corp
COM
$1.4M64.5K
0.7%
Held
19Expand Energy Corporation
COM
$1.4M15.6K
0.7%
Held
20Forrester Resh Inc
COM
$1.1M131.1K
0.5%
Held
21Helix Energy Solutions Grp I
COM
$1.1M124.5K
0.5%
Held
22DXC Technology Co
COM
$907K102.5K
0.5%
Held
23Oshkosh Corp
COM
$883K5.8K
0.4%
Held
24Ttec Hldgs Inc
COM
$496K255.6K
0.2%
Held
25Techtarget Inc
COM NEW
$493K136.9K
0.2%
−33%
Reduced · −66K sh
26Fluor Corp
COM
$343K6.6K
0.2%
Held
27Dhi Group Inc
COM
$314K84.6K
0.2%
Held
28Orasure Technologies Inc
COM
$248K55.6K
0.1%
Held
29Arhaus Inc
COM CL A
$104K12.3K
0.1%
Held
30Oil STS Intl Inc
COM
$93K11.6K
0.0%
Held
31Talkspace Inc
COM
$60K11.6K
0.0%
Held
32NN Inc
COM
$49K13.6K
0.0%
Held
33Cytomx Therapeutics Inc.
COM
$47K12.6K
0.0%
Held
34W & T Offshore Inc
COM
$43K13.6K
0.0%
Held
35Conduent Inc
COM
$26K17.6K
0.0%
New
New position
Showing all 35 positions
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Filing history

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

QuarterAs ofFiledPositionsValueForm
Q2 2026Jun 30, 2026Aug 11, 202635$201.4M13F-HR
Q1 2026Mar 31, 2026May 13, 202646$201.5M13F-HR
Q4 2025Dec 31, 2025Feb 13, 202647$206.0M13F-HR
Q3 2025Sep 30, 2025Nov 12, 202552$234.0M13F-HR
Q2 2025Jun 30, 2025Aug 11, 202549$188.2M13F-HR
Q1 2025Mar 31, 2025May 13, 202557$183.2M13F-HR
Q4 2024Dec 31, 2024Feb 13, 202551$180.2M13F-HR
Q3 2024Sep 30, 2024Nov 13, 202454$176.5M13F-HR

Data source

Holdings from SEC EDGAR 13F-HR filings, updated quarterly, filed up to 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.