Brian Taylor Slingsby
CIK 1963901 · last filed 2026-09-24
Brian Taylor Slingsby is a corporate insider who has filed 9 SEC Form 4 insider transactions across 1 company since 2023. The most recent filing shows the insider sold $3.0M of MLYS on Sep 24, 2026. Across all open-market trades the lifetime net is −$46.0M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $125.4M across reported positions. 10 SEC filings were submitted jointly with Catalys Pacific Fund, LP.
"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.
MLYS 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
150 N. RADNOR CHESTER RD, STE. F200
RADNOR, PA 19087
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| MLYS | Director | 7,805,718 | $16.07 | $125.40M | -$46.03M | 9 | 2026-09-24 |
Recent Filings
9 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-09-24 | MLYS | Sell (S) | −104,320 | -$3.01M | EDGAR |
| 2026-02-20 | MLYS | Mixed | +6,200 | $0 | EDGAR |
| 2025-11-21 | MLYS | Sell (S) | −1,000,000 | -$43.35M | EDGAR |
| 2025-04-25 | MLYS | Buy (P) | +259,259 | $3.50M | EDGAR |
| 2025-02-24 | MLYS | Mixed | — | $0 | EDGAR |
| 2024-07-26 | MLYS | Sell (S) | −550,000 | -$7.18M | EDGAR |
| 2023-07-14 | MLYS | Other (J) | — | $0 | EDGAR |
| 2023-02-16 | MLYS | Mixed | +4,564,093 | $4.00M | EDGAR |
| 2023-02-13 | MLYS | Grant (A) | — | $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.