Mark Thierer
CIK 1334925 · Interim Chief Exec Officer · last filed 2026-01-23
"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
$1.45M
Companies
6
Total Filings
53
Lifetime Open-Market Net
-$70.02M
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 |
|---|---|---|---|---|---|---|---|
| PIIIW | Director | 21,182 | $0.01 | $244 | $0 | 5 | 2026-01-23 |
| Discover Financial Services (DFS) Delisted | Director | 24,563 | $200.05 | $4.91M | $0 | 10 | 2023-05-15 |
| XERS | Director | — | $8.40 | — | $0 | 2 | 2020-06-04 |
| XRAY | Interim Chief Exec Officer | 103,198 | $14.09 | $1.45M | $5.08M | 5 | 2018-02-27 |
| Catamaran Corp (CTRX) Delisted | President & CEO | 0 | — | — | -$23.68M | 12 | 2015-07-23 |
| Catamaran Corp (SXCI) Delisted | President & CEO | 95,408 | — | — | -$51.43M | 19 | 2012-06-06 |
Recent Filings · Page 2 of 6
53 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 |
|---|---|---|---|---|---|
| 2019-10-02 | XERS | Grant (A) | — | $0 | EDGAR |
| 2019-05-20 | Discover Financial Services (DFS) Delisted | Grant (A) | +1,920 | $0 | EDGAR |
| 2018-05-04 | Discover Financial Services (DFS) Delisted | Grant (A) | +1,985 | $0 | EDGAR |
| 2018-02-27 | XRAY | Tax (F) | −16,128 | -$922.2K | EDGAR |
| 2018-01-16 | XRAY | Grant (A) | +56 | $0 | EDGAR |
| 2017-11-14 | XRAY | Buy (P) | +77,000 | $5.08M | EDGAR |
| 2017-10-17 | XRAY | Grant (A) | +61 | $0 | EDGAR |
| 2017-10-02 | XRAY | Grant (A) | +42,208 | $0 | EDGAR |
| 2017-05-12 | Discover Financial Services (DFS) Delisted | Grant (A) | +2,324 | $0 | EDGAR |
| 2016-05-16 | Discover Financial Services (DFS) Delisted | Grant (A) | +2,350 | $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.