William Mariner Greenman
CIK 1377258 · President and CEO · last filed 2026-07-02
William Mariner Greenman is a President and CEO who has filed 76 SEC Form 4 insider transactions across 3 companies since 2007. The most recent filing, for CERS, was dated Jul 2, 2026. Across all open-market trades the lifetime net is −$6.5M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $15.1M across reported positions.
"Disclosed insider exposure" sums this person's most-recently-reported share counts across each company they're an insider in, multiplied by the current underlying price. It is not net worth — it misses retail holdings, private investments, real estate, index funds, and any company where the person isn't an SEC-reporting insider. For informational purposes only.
$15.05M
3
76
-$6.54M
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| CERS | President and CEO | 5,154,955 | $2.92 | $15.05M | -$6.47M | 61 | 2026-07-02 |
| CHINOOK THERAPEUTICS, INC. (KDNY) Delisted | Director | 0 | $40.39 | $0 | -$26.9K | 6 | 2023-08-11 |
| CHINOOK THERAPEUTICS, INC. (ADRO) Delisted | Director | 19,835 | — | — | -$41.0K | 9 | 2020-05-28 |
Recent Filings
76 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-07-02 | CERS | Mixed | −294,419 | -$299.9K | EDGAR |
| 2026-03-16 | CERS | Sell (S) | −447,757 | -$742.0K | EDGAR |
| 2026-03-09 | CERS | Mixed | +115,083 | -$156.8K | EDGAR |
| 2026-03-04 | CERS | Grant (A) | +1,200,000 | $0 | EDGAR |
| 2025-03-17 | CERS | Sell (S) | −193,913 | -$281.2K | EDGAR |
| 2025-03-10 | CERS | Mixed | +1,079,758 | -$91.4K | EDGAR |
| 2025-03-05 | CERS | Mixed | +34,614 | -$35.7K | EDGAR |
| 2025-02-28 | CERS | Grant (A) | — | $0 | EDGAR |
| 2024-03-14 | CERS | Mixed | −61,260 | -$256.4K | EDGAR |
| 2024-03-05 | CERS | Grant (A) | +575,000 | $0 | EDGAR |
Notice (144 / 144/A): Form 144 is a notice of intent to sell restricted/control stock under Rule 144, filed before the sale; 144/A is an amendment. Many notices are pre-scheduled under Rule 10b5-1 plans. A Form 4 with code S typically follows within a few days when the planned sale executes; missing follow-up Form 4s suggest the notice was cancelled or modified.