Montauk Renewables, Inc.
US ˙ NasdaqCM ˙ US61218C1036

SecurityMNTK / Montauk Renewables, Inc.
InstitutionCitigroup Inc
Latest Disclosed Ownership15,781 shares
Latest Disclosed Value $ 18,148
Citigroup Inc reports 117.28% increase in ownership of MNTK / Montauk Renewables, Inc.

On May 11, 2026 - Citigroup Inc filed a 13F-HR form disclosing ownership of 15,781 shares of Montauk Renewables, Inc. (US:MNTK) valued at $18,148 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 7,263 shares of Montauk Renewables, Inc.. This represents a change in shares of 117.28% during the quarter. The current value of the position is $26,749 USD.

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.

Upgrade to unlock premium data and export to Excel .

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)
2026-05-11 2026-03-31 13F MONTAUK RENEWABLES COM 61218C103 15,781 8,518 117.28 18 50.00 0.0000
2026-02-13 2025-12-31 13F MONTAUK RENEWABLES COM 61218C103 7,263 -6,427 -46.95 12 -55.56 0.0000
2025-11-10 2025-09-30 13F MONTAUK RENEWABLES COM 61218C103 13,690 -16,095 -54.04 28 -59.09 0.0000
2025-08-11 2025-06-30 13F MONTAUK RENEWABLES COM 61218C103 29,785 -28,973 -49.31 66 -45.90 0.0000
2025-05-12 2025-03-31 13F MONTAUK RENEWABLES COM 61218C103 58,758 -6,140 -9.46 123 -52.71 0.0001
2025-02-12 2024-12-31 13F MONTAUK RENEWABLES COM 61218C103 64,898 11,445 21.41 258 -7.19 0.0002
2024-11-12 2024-09-30 13F MONTAUK RENEWABLES COM 61218C103 53,453 33,848 172.65 278 150.45 0.0002
2024-08-12 2024-06-30 13F MONTAUK RENEWABLES COM 61218C103 19,605 653 3.45 112 42.31 0.0001
2024-05-10 2024-03-31 13F MONTAUK RENEWABLES COM 61218C103 18,952 -15,175 -44.47 79 -74.34 0.0001
2024-02-09 2023-12-31 13F MONTAUK RENEWABLES COM 61218C103 34,127 19,979 141.21 304 137.50 0.0002
2023-12-06 2023-09-30 13F/A-1 MONTAUK RENEWABLES COM 61218C103 14,148 -8,556 -37.68 129 -23.81 0.0001
2023-11-09 2023-09-30 13F MONTAUK RENEWABLES COM 61218C103 14,148 -8,556 129 0.0000
2023-08-10 2023-06-30 13F MONTAUK RENEWABLES COM 61218C103 22,704 11,280 98.74 169 88.76 0.0001
2023-05-11 2023-03-31 13F MONTAUK RENEWABLES COM 61218C103 11,424 8,317 267.69 90 161.76 0.0001
2023-02-09 2022-12-31 13F MONTAUK RENEWABLES COM 61218C103 3,107 536 20.85 34 -24.44 0.0000
2022-11-10 2022-09-30 13F MONTAUK RENEWABLES COM 61218C103 2,571 -2,853 -52.60 45 -18.18 0.0000
2022-08-10 2022-06-30 13F MONTAUK RENEWABLES COM 61218C103 5,424 -39,979 -88.05 55 -89.17 0.0000
2022-05-12 2022-03-31 13F MONTAUK RENEWABLES COM 61218C103 45,403 9,275 25.67 508 36.93 0.0003
2022-02-10 2021-12-31 13F MONTAUK RENEWABLES COM 61218C103 36,128 32,127 802.97 371 724.44 0.0002
2021-11-10 2021-09-30 13F MONTAUK RENEWABLES COM 61218C103 4,001 4,001 45 0.0000
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.