Castor Maritime Inc.

SecurityCTRM / Castor Maritime Inc.
InstitutionGroup One Trading, L.p.
Latest Disclosed Ownership2,691 shares
Latest Disclosed Value $ 5,570
Group One Trading, L.p. ownership in CTRM / Castor Maritime Inc.

On February 11, 2026 - Group One Trading, L.p. filed a 13F-HR form disclosing ownership of 2,691 shares of Castor Maritime Inc. (US:CTRM) valued at $5,570 USD as of December 31, 2025. The entity filed a previous 13F-HR on November 12, 2025 disclosing 2,591 shares of Castor Maritime Inc.. This represents a change in shares of 3.86% during the quarter. The current value of the position is $6,028 USD.

Group One Trading, L.p. has a history of taking positions in derivatives of the underlying security (CTRM) in the form of stock options.

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.

CTRM / Castor Maritime 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)
2026-02-11 2025-12-31 13F CASTOR MARITIME SHS Y1146L208 2,691 100 3.86 6 0.00 0.0000
2025-11-12 2025-09-30 13F CASTOR MARITIME SHS Y1146L208 2,591 217 9.14 5 0.00 0.0000
2025-08-14 2025-06-30 13F CASTOR MARITIME SHS Y1146L208 2,374 -317 -11.78 5 -16.67 0.0000
2025-05-14 2025-03-31 13F CASTOR MARITIME SHS Y1146L208 2,691 2,691 6 0.0000
2025-05-14 2024-12-31 13F/A-1 CASTOR MARITIME SHS Y1146L208 0 -7,245 -100.00 0 -100.00
2025-02-14 2024-12-31 13F CASTOR MARITIME SHS Y1146L208 0 -7,245 0
2024-11-14 2024-09-30 13F CASTOR MARITIME SHS Y1146L208 7,245 4,424 156.82 31 150.00 0.0001
2024-08-14 2024-06-30 13F CASTOR MARITIME SHS Y1146L208 2,821 2,821 13 0.0001
Disclosed Put 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
(%)
2023-05-12 2023-03-31 13F CASTOR MARITIME SHS NEW Put 0 -100.00 0 -100.00 n/a n/a n/a
2023-02-09 2022-12-31 13F CASTOR MARITIME SHS NEW Put 37,500 -50.59 42 -50.59 n/a n/a n/a
2022-11-09 2022-09-30 13F CASTOR MARITIME SHS NEW Put 75,900 -11.64 85 -26.09 n/a n/a n/a
2022-08-11 2022-06-30 13F CASTOR MARITIME SHS NEW Put 85,900 37.00 115 0.00 n/a n/a n/a
2022-05-12 2022-03-31 13F CASTOR MARITIME SHS NEW Put 62,700 -51.84 115 -37.84 n/a n/a n/a
2022-02-11 2021-12-31 13F CASTOR MARITIME SHS NEW Put 130,200 -1.74 185 -42.72 n/a n/a n/a
2021-11-12 2021-09-30 13F CASTOR MARITIME SHS NEW Put 132,500 140.47 323 124.31 n/a n/a n/a
2021-08-10 2021-06-30 13F CASTOR MARITIME SHS NEW Put 55,100 144 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.