Starboard Principal Co LP

CIK 1517139 · last filed 2025-05-16

Starboard Principal Co LP is a corporate insider who has filed 9 SEC Form 4 insider transactions across 7 companies since 2012. The most recent filing, for ACTG, was dated May 16, 2025. Across all open-market trades the lifetime net is +$43.4M, making them a net buyer over the disclosed history. Current disclosed insider exposure totals $40.9M across reported positions.

"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.

Disclosed Exposure

$40.90M

Companies

7

Total Filings

9

Lifetime Open-Market Net

$43.40M

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
ACTG	10%+ Owner	0	$4.49	$0	$0	2	2025-05-16
GDOT		853,129	$13.36	$11.40M	-$6.89M	1	2024-03-08
Mellanox Technologies, Ltd. (MLNX) Delisted	10%+ Owner	3,758,713	—	—	$0	1	2018-03-02
QUANTUM CORP /DE/ (QTM) Delisted	10%+ Owner	534,662	—	—	-$61.30M	2	2016-12-07
WPP	10%+ Owner	1,140,650	$25.86	$29.50M	$5.61M	1	2012-11-02
ODP Corp (ODP) Delisted	10%+ Owner	1,211,793	$28.00	$33.93M	$142.53M	1	2012-09-17
SURMODICS INC (SRDX) Delisted	10%+ Owner	1,406,667	$42.98	$60.46M	-$36.55M	1	2012-08-10

Recent Filings

9 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
2025-05-16	ACTG	Other (J)	—	$0	EDGAR
2024-03-08	GDOT	Sell (S)	−827,187	-$6.89M	EDGAR
2023-07-17	ACTG	Exer (M)	+164,494,380	$600.40M	EDGAR
2018-03-02	Mellanox Technologies, Ltd. (MLNX) Delisted	Exer (X)	+4,600,000	$115.00M	EDGAR
2016-12-07	QUANTUM CORP /DE/ (QTM) Delisted	Sell (S)	−70,650,000	-$64.38M	EDGAR
2013-04-08	QUANTUM CORP /DE/ (QTM) Delisted	Buy (P)	+2,500,000	$3.08M	EDGAR
2012-11-02	WPP	Buy (P)	+675,000	$5.61M	EDGAR
2012-09-17	ODP Corp (ODP) Delisted	Buy (P)	+62,252,829	$142.53M	EDGAR
2012-08-10	SURMODICS INC (SRDX) Delisted	Sell (S)	−2,060,480	-$36.55M	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.