DFX Intelligence

Sean Judge

General Partnerat Castle Island Management, LLC· New York, NY

As of 2026-10-01 · this person's identity; each section below carries its own date

Current roles: 3
Investments attributed: 3
Board seats: 2

Ask DFX about this View relationships Find contacts Investments Board seats

As of 2026-10-01 · this person's identity; each section below carries its own date

What matters now

3 deals
12 months
3 investments attributed in the last 12 months; latest Valinor round ($25M) on 30 Mar 2026.
A partner with a recent deal is actively writing cheques now.
Factfunding announcements and Form D naming the personFor Founders, co-investorsInvestments →
Moved
role ended
Left Castle Island Management, LLC (General Partner) on 30 Sep 2026.
A partner who moved takes relationships and deal flow to the next firm.
FactForm ADV Schedule A and team pagesFor Founders, recruiters, LPsRoles →
2 boards
seats on record
Sits on 2 boards on record, the latest Cyclops on 15 Jul 2026.
Board seats show where this partner holds governance, not only a cheque.
FactForm D directors and board-seat attributionsFor Founders, co-investorsBoard seats →

Relationship network

6 connected entities3 observed investment recordsinvestment records 2025 to 2026

From the roles sources name this person in, the investments a source attributes to them, and the boards and funds Form D names them on.

Click any name or line for the investment records and sources behind it. Line weight is investment records together; dashed lines are inferred.

Reading the network

Organization
Company
Fund or vehicle

Venture relationships are not scored. Each line names its claim: a round led or joined, a board seat or a filing that names the firm, a listing on a portfolio page (dated by when DFX saw it, never by when the investment was made), a disclosed LP commitment, or a co-investor pair counted from observed participations. Observed means a named source says so; Derived means DFX counted it from observed rows; Inferred means a match that may be wrong.

Darker lines were active in the last 24 months or are current; lighter lines are older or undated.

Ask DFX about this network

Which companies and boards is Sean Judge connected to?

How am I connected?

Name your firm, a company or a person, and DFX finds the published routes to Sean Judge: a shared portfolio company or board, a prior employer, a co-investor, a shared LP or service provider. Every step is a filed or published record with its source; none is a guess about who knows whom.

See how you connect to Sean Judge

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Drawing the relationship network…

Roles

2 current, 1 past

Castle Island General Partner
? to present · “said Sean Judge, General Partner at Castle Island Ventures. Starting”
Fact Press release
Castle Island Management, LLC General Partner
? to present · “team page: Sean Judge / General Partner”
Fact Firm website
Castle Island Management, LLC General Partner
? to Sep 30, 2026 · “was on the team page; absent on 2026-09-30”
Inference Firm website

Investments attributed to this person

Company	Round	Investor	Attribution	Date	Source
Valinor	Funding round · $25.0M	Castle Island Management, LLC	confirmed	Mar 30, 2026	Fact prnewswire.com
Cyclops, Inc.	Funding round · $8.0M	Castle Island	confirmed	Mar 4, 2026	Fact prnewswire.com
Cyclops, Inc.	Form D equity offering · $8.0M	Castle Island	strongly supported · board	Nov 24, 2025	Inference sec.gov

Board seats and vehicles

2 boards, 2 vehicles

Cyclops, Inc. Director Jul 15, 2026 Fact
Valinor Director Feb 5, 2026 Fact
Castle Island Ventures IV, L.P. Executive Officer Sep 29, 2025
Castle Island Ventures IV Feeder, L.P. Executive Officer Oct 30, 2025

Timeline

4 dated entries: events, attributed deals, board seats and role changes

Sep 30, 2026
Left Castle Island Management, LLC as General Partner
Role ended Inference Castle Island Management, LLC Firm website
Mar 30, 2026
Funding round in Valinor (Castle Island Management, LLC)
Attributed investment Fact Valinor Press release
Mar 4, 2026
Funding round in Cyclops, Inc. (Castle Island)
Attributed investment Fact Cyclops, Inc. Press release
Nov 24, 2025
Form D equity offering in Cyclops, Inc. (Castle Island)
Attributed investment Inference Cyclops, Inc. Form D

Record history

3 identity changes, 1 dated event on the change ledger, latest event first

Merged in
2026-10-01
Event retracted
2026-10-01
Merged in
2026-09-30

+1 more change on this record's ledger

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The ledger records every merge, rename and reclassification this record went through and the dated filings observed on it, so the identity on this page can be traced to the records it was built from. The ledger's own sentences name other records, so they show with the names.