MEDIAALPHA INC-CLASS A · CUSIP 58450V104 · CIK 776867
As of 2026-06-30, WHITE MOUNTAINS INSURANCE GROUP LTD reported 17.86M MAX (shares), valued at $224.46M, or 57.03% of its reported non-derivative portfolio. Filed 2026-08-12.
Verify history & sources →Shares unchanged; reported value increased 35.16%, and weight changed +4.04 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds.
Left: % · Right: Shares · Independently scaled axes
Exact data and methodology
Axes scale independently; a crossing does not mean equal values. Weight uses each quarter's total reported non-derivative value. Same CUSIP; missing quarters are gaps, not zero. Revised history may include later disclosures.
| Quarter | Weight | Quantity | Source |
|---|---|---|---|
| Q2 2026 | 57.03% | 17,856,614 | SEC filing ↗Filed Aug 12, 2026 |
| Q1 2026 | 52.99% | 17,856,614 | SEC filing ↗Filed May 12, 2026 |
| Q4 2025 | 88.28% | 17,856,614 | SEC filing ↗Filed Feb 12, 2026 |
| Q3 2025 | 100.00% | 17,856,614 | SEC filing ↗Filed Nov 13, 2025 |
| Q2 2025 | 100.00% | 17,856,614 | SEC filing ↗Filed Aug 11, 2025 |
| Q1 2025 | 57.70% | 17,856,614 | SEC filing ↗Filed May 12, 2025 |
| Q4 2024 | 47.31% | 17,856,614 | SEC filing ↗Filed Feb 12, 2025 |
| Q3 2024 | 59.53% | 17,856,614 | SEC filing ↗Filed Nov 12, 2024 |
| Q2 2024 | 53.00% | 17,856,614 | SEC filing ↗Filed Aug 8, 2024 |
| Q1 2024 | 75.44% | 22,856,814 | SEC filing ↗Filed May 9, 2024 |
| Q4 2023 | 64.91% | 22,856,814 | SEC filing ↗Filed Feb 13, 2024 |
| Q3 2023 | 42.82% | 22,856,814 | SEC filing ↗Filed Nov 9, 2023 |
History & evidence by quarter
| Quarter | Weight | Quantity | Value | Change explained | Source |
|---|---|---|---|---|---|
| Q3 2023 | 42.82% | 22,856,814 | $188.80M | The prior quarter is outside the free window. Sign in for the comparison. | SEC filing ↗ Filed Nov 9, 2023 |
| Q4 2023 | 64.91% | 22,856,814 | $254.85M | Shares unchanged; reported value increased 34.99%, and weight changed +22.09 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 13, 2024 |
| Q1 2024 | 75.44% | 22,856,814 | $465.59M | Shares unchanged; reported value increased 82.69%, and weight changed +10.53 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 9, 2024 |
| Q2 2024 | 53.00% | 17,856,614 | $235.17M | Shares decreased 21.88%; reported value decreased 49.49%, and weight changed -22.44 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 8, 2024 |
| Q3 2024 | 59.53% | 17,856,614 | $323.38M | Shares unchanged; reported value increased 37.51%, and weight changed +6.53 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Nov 12, 2024 |
| Q4 2024 | 47.31% | 17,856,614 | $201.60M | Shares unchanged; reported value decreased 37.66%, and weight changed -12.22 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 12, 2025 |
| Q1 2025 | 57.70% | 17,856,614 | $165.00M | Shares unchanged; reported value decreased 18.16%, and weight changed +10.39 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 12, 2025 |
| Q2 2025 | 100.00% | 17,856,614 | $195.53M | Shares unchanged; reported value increased 18.51%, and weight changed +42.30 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 11, 2025 |
| Q3 2025 | 100.00% | 17,856,614 | $203.21M | Shares unchanged; reported value increased 3.93%, and weight changed +0.00 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Nov 13, 2025 |
| Q4 2025 | 88.28% | 17,856,614 | $231.24M | Shares unchanged; reported value increased 13.80%, and weight changed -11.72 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Feb 12, 2026 |
| Q1 2026 | 52.99% | 17,856,614 | $166.07M | Shares unchanged; reported value decreased 28.19%, and weight changed -35.29 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed May 12, 2026 |
| Q2 2026 | 57.03% | 17,856,614 | $224.46M | Shares unchanged; reported value increased 35.16%, and weight changed +4.04 pp. Weight depends on both the security valuation and total portfolio value, not trade proceeds. | SEC filing ↗ Filed Aug 12, 2026 |
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Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.