Donald A Bergstrom
CIK 1709772 · President, R&D · last filed 2026-09-09
Donald A Bergstrom is a President, R&D who has filed 66 SEC Form 4 insider transactions across 3 companies since 2018. The most recent filing shows the insider sold $161.8K of RLAY on Sep 9, 2026. Across all open-market trades the lifetime net is −$12.1M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $7.3M 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.
Charts
Trading activity, where the exposure sits, and each trade against the stock price.
RLAY price and trades
Daily close with each Form 4 filing on this company marked: green = open-market buy, red = open-market sale, purple = grants, exercises, gifts and other non-market transactions. Marker size scales with the dollar value.
Shares held
Shares owned after each reported transaction on this company (direct holdings as reported).
Open-market buying and selling
by monthDollar value of open-market purchases (code P, up) and sales (code S, down) across all companies, by filing month. Grants, exercises and gifts are excluded.
Exposure by company
latestMost recently reported shares × current price. Faded bars (*) have had no filing in 3 years, so the person may no longer hold them. Click a bar to chart that company.
Filer Profile
CAMBRIDGE, MA 02139
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| RLAY | President, R&D | 399,130 | $18.19 | $7.26M | -$12.11M | 59 | 2026-09-09 |
| Fusion Pharmaceuticals Inc. (FUSN) Delisted | Director | — | $21.55 | — | $0 | 5 | 2024-06-04 |
| Mersana Therapeutics, Inc. (MRSN) Delisted | Chief Medical Officer | — | $29.08 | — | $0 | 1 | 2018-02-06 |
Recent Filings
66 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-09-09 | RLAY | Sell (S) | −8,530 | -$161.8K | EDGAR |
| 2026-07-30 | RLAY | Sell (S) | −2,237 | -$41.6K | EDGAR |
| 2026-07-08 | RLAY | Sell (S) | −8,660 | -$162.0K | EDGAR |
| 2026-06-24 | RLAY | Mixed | — | -$1.20M | EDGAR |
| 2026-06-22 | RLAY | Notice (144) | −110,646 | -$1.76M | EDGAR |
| 2026-01-29 | RLAY | Sell (S) | −21,581 | -$166.7K | EDGAR |
| 2026-01-15 | RLAY | Grant (A) | — | $0 | EDGAR |
| 2025-10-30 | RLAY | Sell (S) | −30,897 | -$225.2K | EDGAR |
| 2025-07-30 | RLAY | Sell (S) | −30,770 | -$113.5K | EDGAR |
| 2025-04-30 | RLAY | Sell (S) | −31,562 | -$95.4K | 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.