Mark S Shapiro
CIK 1345978 · See Remarks · last filed 2026-08-19
Mark S Shapiro is a corporate insider who has filed 140 SEC Form 4 insider transactions across 9 companies since 2007. The most recent filing, for TKO, was dated Aug 19, 2026. Across all open-market trades the lifetime net is −$58.7M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $37.8M across reported positions. 24 SEC filings were submitted jointly with Endeavor Group Holdings, Inc.
"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.
EDR 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
21300 REDSKIN PARK DRIVE
ASHBURN, VA 20147
Holdings By Company
| Symbol | Role | Shares | Price | Disclosed Exposure | Lifetime OM Net | Filings | Latest Filed |
|---|---|---|---|---|---|---|---|
| TKO | See Remarks | 166,191 | $176.81 | $29.38M | -$18.21M | 11 | 2026-08-19 |
| EQUITY RESIDENTIAL (EQR) Delisted | Director | 23,636 | $63.66 | $1.50M | -$4.36M | 29 | 2026-06-23 |
| Endeavor Group Holdings, Inc. (EDR) Delisted | See Remarks | 251,990 | $29.25 | $7.37M | -$34.67M | 14 | 2025-02-25 |
| LYV | Director | 45,492 | $174.71 | $7.95M | -$1.66M | 16 | 2021-06-11 |
| Frontier Communications Parent, Inc. (FTR) Delisted | Director | 2,522 | — | — | $498.9K | 30 | 2019-04-02 |
| Frontier Communications Parent, Inc. (FTRPR) Delisted | Director | — | — | — | $0 | 6 | 2018-04-03 |
| PZZA | Director | 25,070 | $18.56 | $465.3K | -$448.9K | 11 | 2018-03-05 |
| Frontier Communications Parent, Inc. (FTRP.R) Delisted | Director | — | — | — | $0 | 4 | 2016-04-04 |
| Six Flags Entertainment Corp/OLD (SIX) Delisted | President, CEO | 6,610,384 | $32.00 | $211.53M | $128.2K | 4 | 2007-11-15 |
Recent Filings
140 filings| Filed | Symbol | Action | Net Shares | Net $ | Link |
|---|---|---|---|---|---|
| 2026-08-19 | TKO | Mixed | +17,864 | -$3.72M | EDGAR |
| 2026-06-23 | EQUITY RESIDENTIAL (EQR) Delisted | Grant (A) | — | $0 | EDGAR |
| 2026-05-13 | TKO | Buy (P) | +10,807 | $2.00M | EDGAR |
| 2026-01-22 | TKO | Mixed | +13,558 | -$2.90M | EDGAR |
| 2026-01-20 | TKO | Notice (144) | −27,921 | -$5.68M | EDGAR |
| 2026-01-15 | TKO | Notice (144) | −32,022 | -$6.54M | EDGAR |
| 2026-01-05 | TKO | Mixed | +31,165 | -$6.54M | EDGAR |
| 2025-08-19 | TKO | Grant (A) | — | $0 | EDGAR |
| 2025-07-03 | EQUITY RESIDENTIAL (EQR) Delisted | Grant (A) | — | $0 | EDGAR |
| 2025-03-26 | — | Mixed | −198,167 | -$9.55M |
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.