Stockbridge Partners LLC

CIK 1505183 · last filed 2021-12-16

Stockbridge Partners LLC is a corporate insider who has filed 16 SEC Form 4 insider transactions across 3 companies since 2011. The most recent filing, for TDG, was dated Dec 9, 2025. Across all open-market trades the lifetime net is −$787.8M, making them a net seller over the disclosed history. Current disclosed insider exposure totals $1.24B 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

$1.24B

Companies

3

Total Filings

16

Lifetime Open-Market Net

-$787.77M

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
WMS	10%+ Owner	6,429,372	$140.13	$900.95M	-$939.38M	1	2021-12-16
MATTRESS FIRM HOLDING CORP. (MFRM) Delisted	10%+ Owner	4,681,510	—	—	$81.51M	1	2016-03-30
CRI	10%+ Owner	7,935,676	$42.85	$340.08M	$70.10M	1	2011-09-06

Recent Filings

16 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
2025-12-09	TDG	Notice (144)	−100,000	-$134.72M	EDGAR
2025-09-12	TDG	Notice (144)	−10,000	-$12.87M	EDGAR
2025-06-10	TDG	Notice (144)	−65,000	-$95.28M	EDGAR
2025-03-06	TDG	Notice (144)	−100,000	-$137.50M	EDGAR
2024-12-12	TDG	Notice (144)	−45,000	-$56.10M	EDGAR
2024-06-07	TDG	Notice (144)	−100,000	-$133.47M	EDGAR
2024-02-28	WMS	Notice (144)	−762,895	-$125.04M	EDGAR
2024-02-27	TDG	Notice (144)	−300,000	-$356.22M	EDGAR
2023-12-12	TDG	Notice (144)	−25,000	-$24.81M	EDGAR
2023-09-05	WMS	Notice (144)	−425,000	-$54.47M	EDGAR

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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.