Mitsui Sumitomo Insurance Co Ltd: Insider Trades
Every open-market purchase and sale Mitsui Sumitomo Insurance Co Ltd reported on Form 4 since Feb 12, 2026, with how the stock moved after each purchase.
Our read on Mitsui Sumitomo Insurance Co Ltd's trades
Of 13 purchases we can measure six months on, 1 were followed by a rise; the average move was -2.7%, and 0 of 13 beat the S&P 500.
Track record of purchases
Of 13 purchases we can measure after 6 months, 0 beat the S&P 500. On average the stock did 15.0 percentage points worse than the index.
| After | Purchases measured | Average change | Median | Vs. S&P 500 | Rose |
|---|---|---|---|---|---|
| 1 week | 13 | +1.3% | +2.5% | +1.7% | 10 of 13 |
| 1 month | 13 | −5.5% | −7.2% | −0.7% | 1 of 13 |
| 3 months | 7 | −11.4% | −11.3% | −21.2% | 0 of 7 |
| 6 months | 13 | −2.7% | −3.3% | −15.0% | 1 of 13 |
Change in the stock price from the price paid to the closest weekly price about 1 week, 1 month, 3 months, 6 months and 1 year later, from SEC fails-to-deliver data. "Vs. S&P 500" subtracts the change in the SPY ETF over the same weeks. Dividends are not included, and purchases with a possible stock split in between are skipped. Past results do not predict future ones. How we measure this
All reported trades
| Filed | Ticker | Role | Type | Value | Score | 3 mo. after |
|---|---|---|---|---|---|---|
| Mar 3 | WRB | 10% owner | ▲ BUY10b5-1 | $8.10M | 5 | −12.0% |
| Mar 3 | WRB | 10% owner | ▲ BUY10b5-1 | $10.6M | 5 | −12.9% |
| Feb 27 | WRB | 10% owner | ▲ BUY10b5-1 | $10.5M | 8 | −11.3% |
| Feb 27 | WRB | 10% owner | ▲ BUY10b5-1 | $11.0M | 8 | −11.3% |
| Feb 25 | WRB | 10% owner | ▲ BUY10b5-1 | $12.1M | 8 | −11.0% |
| Feb 25 | WRB | 10% owner | ▲ BUY10b5-1 | $11.7M | 8 | −10.3% |
| Feb 25 | WRB | 10% owner | ▲ BUY10b5-1 | $15.7M | 8 | −10.7% |
| Feb 20 | WRB | 10% owner | ▲ BUY10b5-1 | $11.4M | 8 | |
| Feb 20 | WRB | 10% owner | ▲ BUY10b5-1 | $24.4M | 8 | |
| Feb 18 | WRB | 10% owner | ▲ BUY10b5-1 | $20.1M | 8 | |
| Feb 18 | WRB | 10% owner | ▲ BUY10b5-1 | $20.0M | 8 | |
| Feb 13 | WRB | 10% owner | ▲ BUY10b5-1 | $1.40M | 3 | |
| Feb 13 | WRB | 10% owner | ▲ BUY10b5-1 | $1.44M | 3 |
Names come from the filings. Different people can share a name, so we group trades by the SEC's reporting-owner number (CIK) instead.
Sources
- Form 4: WRB, purchase of 112,176 shares · filed 2026-03-03
- Form 4: WRB, purchase of 146,000 shares · filed 2026-03-03
- Form 4: WRB, purchase of 147,000 shares · filed 2026-02-27
- Form 4: WRB, purchase of 153,000 shares · filed 2026-02-27
- Form 4: WRB, purchase of 168,868 shares · filed 2026-02-25
- Form 4: WRB, purchase of 164,786 shares · filed 2026-02-25
- Form 4: WRB, purchase of 220,000 shares · filed 2026-02-25
- Form 4: WRB, purchase of 160,582 shares · filed 2026-02-20
The 8 most recent filings; every trade in the table links to its own Form 4.
About this page
Insider trades reported on SEC Form 4: when the people who run a company buy or sell its shares with their own money.
How to read it
- Form 4
- The form a company insider (officer, director or owner of more than 10%) must file with the SEC within two business days of buying or selling the company's shares.
- Buy (P) and Sell (S)
- Open-market purchases and sales. Gifts, option exercises and automatic tax withholding are left out because they say little about what the insider thinks.
- Value
- Shares times price, as reported on the filing.
- 10b5-1
- A trade made under a plan set up in advance. Planned sales are common and usually say less than an unplanned purchase.
- Late filing
- A Form 4 filed more than two business days after the trade.
- Vs. S&P 500
- How the stock did after the trade minus how the overall market did in the same weeks.
A real example
In January 2016, when bank stocks were falling, JPMorgan Chase CEO Jamie Dimon bought 500,000 JPMorgan shares with his own money, worth about $26 million. His Form 4 made the purchase public within days, and investors read it as a strong sign of confidence.
Explain it like I'm 13
If the coach of a team bets his own allowance that his team will win, that tells you something. A Form 4 is the note a company boss must hand in whenever he buys or sells his own company's shares, so everyone can see it.
Data from public SEC filings and congressional reports. Information, not investment advice. Check every number against the filing linked on the page.