ROBERT H NIEHAUS

CIK 1241677 · Chairman, GCP · last filed 2026-08-19

"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

$46.16M

Companies

11

Total Filings

111

Lifetime Open-Market Net

-$89.29M

Filer Profile

Reported Address
C/O IRIDIUM COMMUNICATIONS INC.
1676 INTERNATIONAL DRIVE, SUITE 1100
MCLEAN, VA 22102
Related Filers
GREENHILL & CO INC — 34 joint filings, latest 2010-02-04
GCP Capital Partners (Cayman) IV, L.P. — 14 joint filings, latest 2023-03-13
GCP Capital Partners IV, L.P. — 14 joint filings, latest 2023-03-13
Greenhill Capital Partners (Cayman Islands) III, L.P. — 14 joint filings, latest 2023-03-13
Greenhill Capital Partners (Employees) III, L.P. — 14 joint filings, latest 2023-03-13
Greenhill Capital Partners (GHL) III, L.P. — 14 joint filings, latest 2023-03-13
Greenhill Capital Partners III, L.P. — 14 joint filings, latest 2023-03-13
GCP MANAGING PARTNER, L.P. — 13 joint filings, latest 2008-06-19
Profile details as reported on the filer's SEC submissions — for individual insiders the address is often in care of the issuer. Related filers are identified from jointly filed SEC submissions and shared reported addresses. View filings on SEC EDGAR.

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
IRDM Director 266,910 $48.75 $13.01M -$14.64M 42 2026-08-19
ZETA Director 671,772 $29.45 $19.78M -$24.97M 11 2026-07-02
HEARTLAND PAYMENT SYSTEMS INC (HPY) Delisted Director 112,722 — — -$4.75M 23 2016-03-11
GREENHILL & CO INC (GHL) Delisted Chairman, GCP 125,631 $14.99 $1.88M -$47.09M 11 2010-02-04
Iridium Communications Inc. (IRDMW) Delisted Director — — — $0 1 2009-09-30
Iridium Communications Inc. (GHQ.WS) Delisted Senior Vice President 398,276 — — $1.94M 5 2009-09-02
EXCO RESOURCES INC (XCO) Delisted Director 15,622 — — $0 9 2009-04-03
Crusader Energy Group Inc. (KRU) Delisted Director 126,596 — — $210.1K 2 2008-12-08
Iridium Communications Inc. (GHQ.U) Delisted Senior Vice President 200,000 — — $0 1 2008-03-13
CCI Director 197,054 $67.84 $13.37M $0 1 2007-03-14
AMERICAN ITALIAN PASTA CO (ECR) Delisted Director 1,325 — — $0 1 2007-02-20

Recent Filings · Page 4 of 12

111 filings
Insider 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
2023-02-17 ZETA Sell (S) −980,735 -$10.02M EDGAR
2023-01-25 ZETA Sell (S) −625,177 -$5.67M EDGAR
2023-01-09 IRDM Grant (A) +4,841 $57.5K EDGAR
2022-08-08 ZETA Sell (S) −1,400,000 -$9.84M EDGAR
2022-08-04 IRDM Sell (S) −30,000 -$1.36M EDGAR
2022-07-06 ZETA Grant (A) +35,128 $0 EDGAR
2022-01-07 IRDM Grant (A) +6,063 $57.5K EDGAR
2021-08-04 IRDM Mixed — -$1.03M EDGAR
2021-02-19 IRDM Sell (S) −50,000 -$2.41M EDGAR
2021-01-08 IRDM Grant (A) +4,383 $57.5K EDGAR
Showing 31–40 of 111
Page 4 of 12
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.