Links go to SEC EDGAR or the sponsor. Document dates are the filing's report date (or filing date); an older prospectus is shown with its date and is not a current comprehensive source. Links are checked weekly; failures are flagged.
Sponsor & official fund page
The sponsor's site carries daily NAV, fact sheets, distribution notices (Section 19(a)), tax information and reinvestment-plan terms.
| Document | Date | Filed | Form | Source | Status |
|---|
| Sponsor websitelatest | — | — | — | Sponsor | OK (Oct 4, 2026, 12:16 AM EDT) |
Prospectus & registration statements
Form N-2 and supplements: investment policies, fee table, leverage terms, rights offerings, at-the-market programmes.
| Document | Date | Filed | Form | Source | Status |
|---|
| Prospectus (Rule 424(b)(3)) — DEFINITIVE MATERIALSlatest · filing index | Dec 13, 2021 | Dec 13, 2021 | 424B3 | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
| Registration statement amendment (Form N-2/A) — AMENDED INITIAL REGISTRATION FOR CLOSED END INVESTMENT COMPANIES · filing index | Dec 8, 2021 | Dec 8, 2021 | N-2/A | SEC EDGAR | unchecked |
| Registration statement / prospectus (Form N-2) — INITIAL REGISTRATION FOR CLOSED-END INVESTMENT COMPANIES · filing index | Jun 17, 2021 | Jun 17, 2021 | N-2 | SEC EDGAR | unchecked |
| Registration statement amendment (Form N-2/A) — INITIAL REGISTRATION FOR CLOSED-END INVESTMENT COMPANIES · filing index | Jun 15, 2021 | Jun 15, 2021 | N-2/A | SEC EDGAR | unchecked |
| Prospectus supplement (Rule 497) — SUPPLEMENTARY MATERIALS · filing index | Jul 26, 2018 | Jul 26, 2018 | 497 | SEC EDGAR | unchecked |
| Prospectus supplement (Rule 497) — SUPPLEMENTARY MATERIALS · filing index | Jul 26, 2016 | Jul 26, 2016 | 497 | SEC EDGAR | unchecked |
| Prospectus supplement (Rule 497) — SUPPLEMENTARY MATERIALS · filing index | Jul 21, 2016 | Jul 21, 2016 | 497 | SEC EDGAR | unchecked |
| Prospectus supplement (Rule 497) — DEFINITIVE MATERIALS · filing index | Jul 15, 2016 | Jul 15, 2016 | 497 | SEC EDGAR | unchecked |
Annual reports (N-CSR)
Financial highlights, statements, notes on leverage and fees, distribution sources.
| Document | Date | Filed | Form | Source | Status |
|---|
| Annual shareholder report (Form N-CSR) — CERTIFIED ANNUAL SHAREHOLDER REPORTlatest · filing index | Dec 31, 2025 | Mar 10, 2026 | N-CSR | SEC EDGAR | OK (Oct 11, 2026, 12:16 AM EDT) |
| Annual shareholder report (Form N-CSR) · filing index | Dec 31, 2024 | Mar 10, 2025 | N-CSR | SEC EDGAR | unchecked |
| Annual shareholder report (Form N-CSR) — CERTIFIED ANNUAL SHAREHOLDER REPORT · filing index | Dec 31, 2023 | Mar 6, 2024 | N-CSR | SEC EDGAR | unchecked |
| Annual shareholder report (Form N-CSR) — SPECIAL OPPORTUNITIES FUND, INC. ANNUAL REPORT 12-31-22 · filing index | Mar 6, 2023 | Mar 6, 2023 | N-CSR | SEC EDGAR | unchecked |
| Annual shareholder report (Form N-CSR) — SPECIAL OPPORTUNITIES FUND, INC. ANNUAL REPORT 12-31-21 · filing index | Dec 31, 2021 | Mar 3, 2022 | N-CSR | SEC EDGAR | unchecked |
| Annual shareholder report (Form N-CSR) — SPECIAL OPPORTUNITIES FUND, INC. ANNUAL REPORT 12-31-20 · filing index | Dec 31, 2020 | Mar 8, 2021 | N-CSR | SEC EDGAR | unchecked |
Semi-annual reports (N-CSRS)
| Document | Date | Filed | Form | Source | Status |
|---|
| Semi-annual shareholder report (Form N-CSRS) — CERTIFIED SEMI-ANNUAL SHAREHOLDER REPORTlatest · filing index | Jun 30, 2026 | Sep 4, 2026 | N-CSRS | SEC EDGAR | OK (Oct 11, 2026, 12:18 AM EDT) |
| Semi-annual shareholder report (Form N-CSRS) — SPECIAL OPPORTUNITIES FUND, INC. SEMIANNUAL REPORT 6-30-24 · filing index | Jun 30, 2025 | Sep 5, 2025 | N-CSRS | SEC EDGAR | unchecked |
| Semi-annual shareholder report (Form N-CSRS) — SPECIAL OPPORTUNITIES FUND, INC. SEMIANNUAL REPORT 6-30-24 · filing index | Jun 30, 2024 | Sep 9, 2024 | N-CSRS | SEC EDGAR | unchecked |
| Semi-annual shareholder report (Form N-CSRS) · filing index | Jun 30, 2023 | Sep 6, 2023 | N-CSRS | SEC EDGAR | unchecked |
| Semi-annual shareholder report (Form N-CSRS) — SPECIAL OPPORTUNITIES FUND, INC. SEMIANNUAL REPORT 6-30-22 · filing index | Jun 30, 2022 | Sep 7, 2022 | N-CSRS | SEC EDGAR | unchecked |
| Semi-annual shareholder report (Form N-CSRS) — SPECIAL OPPORTUNITIES FUND, INC. SEMIANNUAL REPORT 6-30-21 · filing index | Jun 30, 2021 | Sep 2, 2021 | N-CSRS | SEC EDGAR | unchecked |
Portfolio holdings (N-PORT)
Monthly portfolio filed quarterly with a ~60-day lag.
| Document | Date | Filed | Form | Source | Status |
|---|
| Monthly portfolio holdings (Form N-PORT)latest · filing index | Jun 30, 2026 | Aug 31, 2026 | NPORT-P | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
| Monthly portfolio holdings (Form N-PORT) · filing index | Mar 31, 2026 | Jun 1, 2026 | NPORT-P | SEC EDGAR | unchecked |
| Monthly portfolio holdings (Form N-PORT) · filing index | Dec 31, 2025 | Feb 3, 2026 | NPORT-P | SEC EDGAR | unchecked |
| Monthly portfolio holdings (Form N-PORT) · filing index | Sep 30, 2025 | Nov 26, 2025 | NPORT-P | SEC EDGAR | unchecked |
| Monthly portfolio holdings (Form N-PORT) · filing index | Jun 30, 2025 | Aug 27, 2025 | NPORT-P | SEC EDGAR | unchecked |
| Monthly portfolio holdings (Form N-PORT) · filing index | Mar 31, 2025 | May 29, 2025 | NPORT-P | SEC EDGAR | unchecked |
Tender offers
Schedule TO filings: pricing formula, size, deadlines, proration.
Proxy statements & reorganisations
Shareholder votes: directors, mergers, liquidations, conversions.
| Document | Date | Filed | Form | Source | Status |
|---|
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENTlatest · filing index | Oct 31, 2025 | Oct 31, 2025 | DEF 14A | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
| Additional proxy materials (DEFA14A) · filing index | May 1, 2025 | May 1, 2025 | DEFA14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Oct 30, 2024 | Oct 31, 2024 | DEF 14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Oct 25, 2023 | Oct 26, 2023 | DEF 14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Nov 9, 2022 | Nov 9, 2022 | DEF 14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Nov 9, 2021 | Nov 9, 2021 | DEF 14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Oct 29, 2020 | Oct 30, 2020 | DEF 14A | SEC EDGAR | unchecked |
| Proxy statement (DEF 14A) — DEFINITIVE PROXY STATEMENT · filing index | Oct 25, 2019 | Oct 31, 2019 | DEF 14A | SEC EDGAR | unchecked |
Current reports (8-K)
| Document | Date | Filed | Form | Source | Status |
|---|
| Current report (8-K) — CURRENT REPORTlatest · filing index | May 11, 2023 | Jun 7, 2023 | 8-K | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
| Current report (8-K) — CURRENT REPORT · filing index | Dec 3, 2019 | Dec 4, 2019 | 8-K | SEC EDGAR | unchecked |
| Current report (8-K) — CURRENT REPORT, ITEMS 9.01 · filing index | Jun 5, 2012 | Jun 5, 2012 | 8-K | SEC EDGAR | unchecked |
| Current report (8-K) — CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF · filing index | Dec 14, 2011 | Dec 14, 2011 | 8-K | SEC EDGAR | unchecked |
| Current report (8-K) — CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF · filing index | Dec 20, 2010 | Dec 20, 2010 | 8-K | SEC EDGAR | unchecked |
| Current report (8-K) — INSURED MUNICIPAL INCOME FUND INC · filing index | Nov 15, 2006 | Nov 21, 2006 | 8-K | SEC EDGAR | unchecked |
Other
| Document | Date | Filed | Form | Source | Status |
|---|
| Proxy voting record (N-PX)latest · filing index | Jun 30, 2026 | Aug 20, 2026 | N-PX | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
| Proxy voting record (N-PX) · filing index | Jun 30, 2025 | Aug 28, 2025 | N-PX | SEC EDGAR | unchecked |
| Proxy voting record (N-PX) · filing index | Jun 30, 2024 | Sep 3, 2024 | N-PX | SEC EDGAR | unchecked |
| Proxy voting record (N-PX) — ANNUAL REPORT OF PROXY VOTING · filing index | Jun 30, 2023 | Aug 28, 2023 | N-PX | SEC EDGAR | unchecked |
| All SEC filings for this fund (EDGAR)latest | — | — | — | SEC EDGAR | OK (Oct 4, 2026, 12:16 AM EDT) |
Not on file for this fund: fact sheets, distribution notices, tax information, reinvestment plan. These are published on the sponsor's site rather than EDGAR; use the sponsor link above.