Castor Maritime Inc.: shareholders and insiders

CTRMNASDAQIndustrials · Deep Sea Foreign Transportation of Freight

Price

$1.31

November 13, 2026Market cap $13M

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What Ploutos Investor adds for Castor Maritime

Part of Ploutos Investor, €9.99 a month

See the plans

The full history: 8 fiscal years, from FY2018
The estimated fair value, with its range and its certainty
The full analysis, 18 a month
More questions to the chat on its filings
Excel with every year
An email when it reports, changes its dividend or an officer buys

Notes on these figures

The reported profit is far larger than a business usually earns on its market value, which usually means one-off or accounting gains. We leave out the P/E and the earnings yield.
Profit over the last twelve months is well above what the business itself earned, because it includes large gains outside the business, such as on investments or from selling a business. The P/E is lower than the business alone would give.
The interest the company pays is far more than the debt we can read would cost, so part of its borrowing is missing from the figures. We leave out the debt, net cash, enterprise value and the multiples built on them.

Insiders and their shares

Purchases and sales by officers and directors, from their own Form 4 filings.

Sorry, we do not have enough data

for purchases and sales by Castor Maritime's insiders

Why?

Castor Maritime's filings

Major holders (over 5%)

Whoever comes to own more than 5% of a class of shares reports it to the SEC on Schedule 13D or 13G. Here is each holder's latest filing.

No filing over 5%

Since Dec 18, 2024 nobody has filed a Schedule 13D or 13G for Castor Maritime shares.

From the Schedule 13D and 13G filed with the SEC since Dec 18, 2024, when they became structured data. A holder who has filed nothing since then is not shown here. A 13D is updated within two business days of any material change, a 13G up to 45 days after the quarter of the change, so the shares are those of the filing. The large managers also appear in the 13Fs.

Well-known managers

Which of the about 30 investment managers we track held the shares at the quarter end, and what they changed from the quarter before.

Sep 30, 2026 quarter end

Citadel Advisors (Griffin)
In the quarter
Renaissance Technologies
In the quarter+33%

Manager	Shares	In the quarter	Value	% of their portfolio
Citadel Advisors (Griffin)	26.1K		$100.0K	0.00%
Renaissance Technologies	86.5K	+33%	$200.0K	0.00%

From the 13Fs managers file with the SEC up to 45 days after each quarter end. They show only long positions on that day, not short sales or what has changed since. No recent 13F: Pershing Square (Ackman), Scion (Burry).

Short interest

How many of the company's shares have been sold borrowed and not yet bought back, twice a month.

On Oct 15, 2026, 0.07% of its shares outstanding were held short, +80.5% since the report before.

Shares held short: 6,556
: 0.07%
Since the report before3,632 on Sep 30, 2026: +80.5%
: under 1
: 48.2K
Report date: Oct 15, 2026

Oct 31, 2023: Shares held short 1.16M
Nov 15, 2023: Shares held short 875.2K
Nov 30, 2023: Shares held short 893.9K
Dec 15, 2023: Shares held short 1.06M
Dec 29, 2023: Shares held short 741.6K
Jan 12, 2024: Shares held short 709.1K
Jan 31, 2024: Shares held short 875.4K
Feb 15, 2024: Shares held short 533.7K
Feb 29, 2024: Shares held short 499.8K
Mar 15, 2024: Shares held short 517.0K
Mar 28, 2024: Shares held short 52.8K
Apr 15, 2024: Shares held short 62.7K
Apr 30, 2024: Shares held short 72.6K
May 15, 2024: Shares held short 54.7K
May 31, 2024: Shares held short 76.2K
Jun 14, 2024: Shares held short 71.1K
Jun 28, 2024: Shares held short 47.4K
Jul 15, 2024: Shares held short 57.0K
Jul 31, 2024: Shares held short 74.2K
Aug 15, 2024: Shares held short 51.0K
Aug 30, 2024: Shares held short 35.6K
Sep 13, 2024: Shares held short 25.0K
Sep 30, 2024: Shares held short 13.4K
Oct 15, 2024: Shares held short 26.8K
Oct 31, 2024: Shares held short 39.3K
Nov 15, 2024: Shares held short 75.5K
Nov 29, 2024: Shares held short 89.6K
Dec 13, 2024: Shares held short 70.2K
Dec 31, 2024: Shares held short 20.0K
Jan 15, 2025: Shares held short 39.8K
Jan 31, 2025: Shares held short 46.6K
Feb 14, 2025: Shares held short 58.9K
Feb 28, 2025: Shares held short 34.3K
Mar 14, 2025: Shares held short 63.3K
Mar 31, 2025: Shares held short 69.2K
Apr 15, 2025: Shares held short 102.8K
Apr 30, 2025: Shares held short 84.7K
May 15, 2025: Shares held short 59.2K
May 30, 2025: Shares held short 64.0K
Jun 13, 2025: Shares held short 45.6K
Jun 30, 2025: Shares held short 54.8K
Jul 15, 2025: Shares held short 41.4K
Jul 31, 2025: Shares held short 50.0K
Aug 15, 2025: Shares held short 55.9K
Aug 29, 2025: Shares held short 36.7K
Sep 15, 2025: Shares held short 38.2K
Sep 30, 2025: Shares held short 14.8K
Oct 15, 2025: Shares held short 16.8K
Oct 31, 2025: Shares held short 18.2K
Nov 14, 2025: Shares held short 45.2K
Nov 28, 2025: Shares held short 30.3K
Dec 15, 2025: Shares held short 21.6K
Dec 31, 2025: Shares held short 13.6K
Jan 15, 2026: Shares held short 4,714
Jan 30, 2026: Shares held short 7,027
Feb 13, 2026: Shares held short 5,402
Feb 27, 2026: Shares held short 5,382
Mar 13, 2026: Shares held short 13.5K
Mar 31, 2026: Shares held short 16.4K
Apr 15, 2026: Shares held short 12.8K
Apr 30, 2026: Shares held short 9,699
May 15, 2026: Shares held short 15.8K
May 29, 2026: Shares held short 8,770
Jun 15, 2026: Shares held short 15.5K
Jun 30, 2026: Shares held short 17.9K
Jul 15, 2026: Shares held short 23.9K
Jul 31, 2026: Shares held short 23.8K
Aug 14, 2026: Shares held short 28.5K
Aug 31, 2026: Shares held short 15.5K
Sep 15, 2026: Shares held short 9,813
Sep 30, 2026: Shares held short 3,632
Oct 15, 2026: Shares held short 6,556

As brokers report them to the regulator twice a month, mid-month and at month end, published about eight business days later. A short position is shares sold borrowed and not yet bought back. The share count is the one the company's market value is figured on, from its filings. Days to cover is the shares held short over the average daily volume of the weeks between two reports.

Short sales in daily trading45.1% of the shares in the last 14 sessions' reported trades were short sales.

In the last 14 sessions, 45.1% of the shares in the reported trades were short sales, against 44.2% in the 14 before.

Last 14 sessionsOct 27, 2026 – Nov 13, 2026: 45.1%
The 14 beforeOct 7, 2026 – Oct 26, 2026: 44.2%
Change: +0.9 pts
Short sales a dayon average, of 24.2K shares: 10.9K
More than atof 3,649 US-listed companies, same days: 33%
Median of alleight in ten from 34.6% to 63.4%: 50.1%

This is not the number of shares sold short today: it measures short sales within each day's trading, and only trades made off the exchanges. Much of it is market makers, who sell shares they do not have to fill buyers' orders and cover soon after, so for a heavily traded stock the share is often around half.

Institutional investors by quarter

Every manager that reports positions to the SEC (Form 13F), quarter by quarter: how many hold the stock, how many shares and dollars between them, and who entered, left, added or trimmed during the quarter.

25 Managers, Q2 2026$902.9K Value of their positions

Institutional investors by quarter

The fund managers holding CTRM, quarter by quarter, from Q2 2021 to Q2 2025, 17 more quarters

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Q2 2026: 25 managers held 430.2K shares, worth $902.9K. During the quarter 8 opened a position, 2 closed one, 4 added and 2 trimmed.

The largest holders, Q2 2026

Towerview
In the quarter
Renaissance Technologies
In the quarter-12%
Citadel Advisors (Griffin)
In the quarter
NewEdge Advisors
In the quarter
Goldman Sachs Group
In the quarter+0.6%
Apriem Advisors
In the quarter
Susquehanna International Group
In the quarter
Centiva Capital
In the quarter+10%
Simplex Trading
In the quarter+45%
TD Waterhouse Canada
In the quarter

Manager	Shares	In the quarter	Value
Towerview	240.0K		$504.0K
Renaissance Technologies	64.8K	-12%	$136.1K
Citadel Advisors (Griffin)	26.1K		$54.5K
NewEdge Advisors	21.9K		$46.0K
Goldman Sachs Group	21.2K	+0.6%	$44.5K
Apriem Advisors	19.0K		$39.9K
Susquehanna International Group	12.6K		$26.2K
Centiva Capital	12.2K	+10%	$25.6K
Simplex Trading	8,510	+45%	$17.9K
TD Waterhouse Canada	2,800		$5.9K

From the SEC's Form 13F data sets, Q3 2025 to Q2 2026: the long positions of every manager with more than $100 million under management, as filed up to 45 days after each quarter end. Short positions and options are not in them. Shares as reported each quarter, not adjusted for splits. The stock is matched by its CUSIP, through the SEC's fails-to-deliver files.

Pay against performance, the say-on-pay vote, buybacks by quarter and trading plans are read for S&P 500 companies only.

The full analysis

What do Castor Maritime's filings show?

Who buys and sells is one part of Castor Maritime's picture. The full Ploutos AI analysis reads everything the company has filed and shows what stands behind it, with a source for every figure.

A fair value range built from the filings
Earnings quality, debt and red flags
Insider and institutional moves
The case for and the case against

Questions about CTRM's shareholders

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Have CTRM's insiders bought or sold?

From – to – Castor Maritime's insiders reported no purchase or sale of shares on the market.

Which well-known managers hold CTRM?

2 of the managers we track held the shares on Sep 30, 2026. The largest position was Renaissance Technologies's, worth $200.0K.

Is every insider transaction a purchase or a sale?

No. Many are part of their pay: share awards, option exercises and shares the company keeps for the tax. Only code P is a purchase with their own money, and code S a sale on the market.

The other pages on US stocks, free to read. On the company pages, the last three fiscal years are open to everyone, five with a free account, and every year with Ploutos Investor.

US stocksThe market today, the sectors, the largest companies and the week's results.The market's sectorsThe 11 sectors side by side: returns, share of the market, median P/E and dividend.Compare stocksTwo companies side by side: price over up to ten years, with and without dividends, and every figure.US dividend stocksEach dividend's yield next to whether the company's cash covers it and whether it was ever cut.

The figures come from the company's SEC filings and the share price, and describe what it has reported. They are not a score or a fair value.