Main Street Capital Corporation
US ˙ NYSE ˙ US56035L1044

SecurityMAIN / Main Street Capital Corporation
InstitutionMillennium Management Llc
ManagerIsrael Englander
Latest Disclosed Ownership359,838 shares
Latest Disclosed Value $ 19,057,020
Millennium Management Llc ownership in MAIN / Main Street Capital Corporation

On May 15, 2026 - Millennium Management Llc filed a 13F-HR form disclosing ownership of 359,838 shares of Main Street Capital Corporation (US:MAIN) valued at $19,057,020 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 247,063 shares of Main Street Capital Corporation. This represents a change in shares of 45.65% during the quarter. The current value of the position is $18,718,773 USD.

Millennium Management Llc has a history of taking positions in derivatives of the underlying security (MAIN) 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.

MAIN / Main Street Capital Corporation 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)
2026-05-15 2026-03-31 13F MAIN STR CAP COM 56035L104 359,838 112,775 45.65 19,057 27.73 0.0079
2026-02-17 2025-12-31 13F MAIN STR CAP COM 56035L104 247,063 200,867 434.81 14,920 408.00 0.0063
2025-11-14 2025-09-30 13F MAIN STR CAP COM 56035L104 46,196 31,727 219.28 2,938 243.51 0.0013
2025-08-14 2025-06-30 13F MAIN STR CAP COM 56035L104 14,469 -4,692 -24.49 855 -21.05 0.0004
2025-05-15 2025-03-31 13F MAIN STR CAP COM 56035L104 19,161 19,161 1,084 0.0006
2024-05-15 2024-03-31 13F MAIN STR CAP COM 56035L104 0 -143,652 -100.00 0 -100.00
2024-02-14 2023-12-31 13F MAIN STR CAP COM 56035L104 143,652 -144,345 -50.12 6,210 -46.93 0.0027
2023-11-14 2023-09-30 13F MAIN STR CAP COM 56035L104 287,997 -162,990 -36.14 11,701 -35.19 0.0059
2023-08-14 2023-06-30 13F MAIN STR CAP COM 56035L104 450,987 424,983 1,634.30 18,053 1,659.55 0.0089
2023-05-15 2023-03-31 13F MAIN STR CAP COM 56035L104 26,004 -154,620 -85.60 1,026 -84.63 0.0006
2023-02-14 2022-12-31 13F MAIN STR CAP COM 56035L104 180,624 180,624 6,674 0.0037
2022-08-15 2022-06-30 13F MAIN STR CAP COM 56035L104 0 -417,432 -100.00 0 -100.00
2022-05-16 2022-03-31 13F MAIN STR CAP COM 56035L104 417,432 181,595 77.00 17,799 68.23 0.0094
2022-02-14 2021-12-31 13F MAIN STR CAP COM 56035L104 235,837 113,098 92.15 10,580 109.71 0.0054
2021-11-15 2021-09-30 13F MAIN STR CAP COM 56035L104 122,739 59,849 95.16 5,045 95.24 0.0030
2021-08-16 2021-06-30 13F MAIN STR CAP COM 56035L104 62,890 54,742 671.85 2,584 710.03 0.0016
2021-05-17 2021-03-31 13F MAIN STR CAP COM 56035L104 8,148 -254,357 -96.90 319 -96.23 0.0002
2021-02-16 2020-12-31 13F MAIN STR CAP COM 56035L104 262,505 262,505 8,468 0.0061
2020-08-14 2020-06-30 13F MAIN STR CAP COM 56035L104 0 -115,137 -100.00 0 -100.00
2020-05-14 2020-03-31 13F MAIN STR CAP COM 56035L104 115,137 109,325 1,881.02 2,361 840.64 0.0053
2020-02-14 2019-12-31 13F MAIN STREET CAPITAL COM 56035L104 5,812 5,812 251 0.0003
2019-05-14 2019-03-31 13F MAIN STREET CAPITAL COM 56035L104 0 -69,260 -100.00 0 -100.00
2019-02-15 2018-12-31 13F/A-1 MAIN STREET CAPITAL COM 56035L104 69,260 5,186 8.09 2,342 -5.07 0.0037
2019-02-14 2018-12-31 13F MAIN STREET CAPITAL COM 56035L104 69,260 2,342
2018-11-14 2018-09-30 13F MAIN STREET CAPITAL COM 56035L104 64,074 56,545 751.03 2,467 759.58 0.0030
2018-08-14 2018-06-30 13F MAIN STREET CAPITAL COM 56035L104 7,529 -133,208 -94.65 287 -94.47 0.0004
2018-05-15 2018-03-31 13F MAIN STREET CAPITAL COM 56035L104 140,737 140,737 5,193 0.0069
2018-02-14 2017-12-31 13F MAIN STREET CAPITAL COM 56035L104 0 -47,672 -100.00 0 -100.00
2017-11-14 2017-09-30 13F MAIN STREET CAPITAL COM 56035L104 47,672 47,672 1,895 0.0029
2016-08-15 2016-06-30 13F MAIN STREET CAPITAL COM 56035L104 0 -12,432 -100.00 0 -100.00
2016-05-16 2016-03-31 13F MAIN STREET CAPITAL COM 56035L104 12,432 12,432 0.00 390 0.0010
2015-08-14 2015-06-30 13F MAIN STREET CAPITAL COM 56035L104 0 -33,000 -100.00 0 -100.00
2015-05-15 2015-03-31 13F MAIN STREET CAPITAL COM 56035L104 33,000 -91,374 -73.47 1,020 -71.95 0.0019
2015-02-17 2014-12-31 13F MAIN STREET CAPITAL COM 56035L104 124,374 27,349 28.19 3,637 22.33 0.0077
2014-11-14 2014-09-30 13F MAIN STREET CAPITAL COM 56035L104 97,025 25,106 34.91 2,973 25.55 0.0075
2014-08-14 2014-06-30 13F MAIN STREET CAPITAL COM 56035L104 71,919 71,919 2,368 0.0066
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
(%)
2026-05-15 2026-03-31 13F MAIN STR CAP COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2026-02-17 2025-12-31 13F MAIN STR CAP COM Put 141,900 0.00 8,569 -5.03 n/a n/a n/a
2025-11-14 2025-09-30 13F MAIN STR CAP COM Put 141,900 40.50 9,023 51.16 n/a n/a n/a
2025-08-14 2025-06-30 13F MAIN STR CAP COM Put 101,000 93.12 5,969 101.79 n/a n/a n/a
2025-05-15 2025-03-31 13F MAIN STR CAP COM Put 52,300 925.49 2,958 892.62 n/a n/a n/a
2025-02-14 2024-12-31 13F MAIN STR CAP COM Put 5,100 299 n/a n/a n/a
2019-08-15 2019-06-30 13F/A MAIN STREET CAPITAL COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2019-05-14 2019-03-31 13F MAIN STREET CAPITAL COM Put 78,500 2,920 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.