SEIC insider buying and SEC filings, explained
Sei Investments Co. · CIK 350894
Tracked: Forms 3/4/5, 8-K, NT · All filings on sec.gov
Insider activity in the last 12 months
Bought
$0
Insiders who bought
0
Sold (not marked 10b5-1)
$16.2M
Planned sales (10b5-1)
$0
Insider purchases and sales, last 12 months
| Traded | Type | What was filed | Source |
|---|---|---|---|
| Sep 29–30, 2026 | Sale | Alfred P. West Jr. (Chairman Emeritus) sold 33,877 shares between Sep 29 and Sep 30 at about $103.36 ($3.5M). Holdings down <1% to 6,784,574 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Oct 1, 2026, 4:05 PM ET |
| Sep 22, 2026 | Sale | Michael Lane (Executive Vice President) sold 2,400 shares at about $102.78 ($247K). Holdings down 6% to 39,581 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Sep 24, 2026 |
| Jun 26–29, 2026 | Sale | Alfred P. West Jr. (Chairman Emeritus) sold 57,332 shares between Jun 26 and Jun 29 at about $87.26 ($5.0M). Holdings down 1% to 6,818,451 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 29, 2026 |
| Jun 9, 2026 | Sale | William Doran (Director) sold 5,000 shares at $90.50 ($453K). Holdings down 1% to 618,802 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Jun 11, 2026 |
| Apr 23, 2026 | Sale | Philip McCabe (Officer) sold 15,000 shares at about $91.82 ($1.4M). Holdings down 21% to 54,884 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Apr 24, 2026 |
| Mar 10–11, 2026 | Sale | Alfred P. West Jr. (Chairman Emeritus) sold 62,447 shares between Mar 10 and Mar 11 at about $80.12 ($5.0M). Holdings down 1% to 6,875,783 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Mar 12, 2026 |
| Dec 22, 2025 | Sale | William Doran (Director) sold 7,000 shares at $83.85 ($587K). Holdings down 1% to 623,802 shares. Not marked as a 10b5-1 plan trade. | SEC filing Filed Dec 23, 2025 |
62 routine transactions (such as grants, option exercises or tax withholding) are not listed.
Cluster buys
No cluster buys in the last 12 months.
Red flags
No red flags in the last 12 months.
Key events
No key events in the last 12 months.
8-K filings, last 12 months
No 8-K filings in the last 12 months.
Red flags are objective triggers only: the item or form filed, never an opinion.
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