MARK A MCCOLLUM
CIK 1215888 · President and CEO · last filed 2026-06-05
"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.
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Disclosed Exposure
$10.55M
Companies
9
Total Filings
87
Lifetime Open-Market Net
-$11.99M
Holdings By Company
Latest on-record share count from this person's most recent non-derivative Form 4 transaction in each company. Disclosed exposure = shares × current underlying price.
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| SDRL | Director | 7,269 | $41.01 | $298.1K | $0 | 4 | 2026-06-05 |
| OKE | Director | 2,572 | $88.80 | $228.4K | $0 | 2 | 2026-05-22 |
| WLK | Director | 9,656 | $72.16 | $696.8K | $0 | 11 | 2025-08-11 |
| MARATHON OIL CORP (MRO) Delisted | Director | 0 | $28.55 | $0 | $0 | 4 | 2024-11-22 |
| Weatherford International plc (WFT) Delisted | President and CEO | 1,665,615 | — | — | $0 | 5 | 2019-04-25 |
| AROC | Director | 82,751 | $35.30 | $2.92M | $0 | 4 | 2018-04-27 |
| HAL | EVP - Chief Financial Officer | 204,993 | $31.23 | $6.40M | -$11.99M | 45 | 2017-03-01 |
| Archrock, Inc. (EXH) Delisted | Director | 39,195 | — | — | $0 | 7 | 2015-03-05 |
| Archrock Partners, L.P. (EXLP) Delisted | Director | 2,000 | — | — | $0 | 4 | 2009-06-01 |
Recent Filings · Page 2 of 9
87 filingsInsider activity across all companies, newest first. Form 4 rows are post-trade confirmations (buys, sells, grants, exercises). Notice (144) rows are pre-trade notices of intent to sell restricted or control stock under Rule 144 — they may not all execute. Compare adjacent dates to see which notices became actual sales.
| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2023-08-14 | WLK | Mixed | +1,446 | $0 | EDGAR |
| 2023-03-03 | MARATHON OIL CORP (MRO) Delisted | Grant (A) | +7,754 | $0 | EDGAR |
| 2022-12-02 | MARATHON OIL CORP (MRO) Delisted | Grant (A) | +415 | $0 | EDGAR |
| 2022-08-15 | WLK | Mixed | +1,763 | $0 | EDGAR |
| 2022-03-04 | WLK | Gift (G) | −3,000 | $0 | EDGAR |
| 2021-08-16 | WLK | Mixed | +2,400 | $0 | EDGAR |
| 2020-08-17 | WLK | Mixed | +2,387 | $0 | EDGAR |
| 2019-12-17 | — | Mixed | −1,663,874 | $13.2K | |
| 2019-08-19 | WLK | Mixed | +1,409 | $0 | EDGAR |
| 2019-05-20 | WLK | Exer (M) | +987 | $0 | EDGAR |
Form 4 codes: P = open-market purchase · S = open-market sale · A = grant/award · M = option exercise · F = tax withholding at vest · G = bona-fide gift · D = disposition to issuer · J = other (see filing footnote). Only P / S codes carry directional signal.
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.
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.