Onex Partners V Annex I LP 2026: Is It Legit? Form D Raise, Investors, Who Is Behind It

Q: What is Onex Partners V Annex I LP?

Onex Partners V Annex I LP is an issuer that filed a Form D with the SEC on November 10, 2026. The filing claims 506(b), 3(c)(1).

Q: Is Onex Partners V Annex I LP legit?

AltStreet does not rate legitimacy; it reports the public record. Onex Partners V Annex I LP filed a Form D with the SEC on November 10, 2026 claiming 506(b), 3(c)(1). A Form D is a notice of an exempt offering, not a review or approval of it. AltStreet's enforcement record (SEC, FINRA and state actions) shows no action naming the issuer as of today. Before investing, confirm the filing on EDGAR, check the seller's registration on FINRA BrokerCheck, and read the offering documents, which a Form D does not include.

Q: Is Onex Partners V Annex I LP registered with or approved by the SEC?

No. A Form D is a notice that an issuer is selling securities under an exemption from registration, and the SEC does not review, approve, or pass on the merits of the offering. The filing shows that Onex Partners V Annex I LP claimed 506(b), 3(c)(1) and disclosed the items the form requires, such as the amount sold, the minimum investment, related persons, and anyone paid to sell the securities. It does not verify the issuer's claims or its business.

Q: How much has Onex Partners V Annex I LP raised?

Onex Partners V Annex I LP reported no amount sold as of the Form D filed November 10, 2026.

Q: Who is selling Onex Partners V Annex I LP and how are they paid?

The Form D names no recipient of sales compensation, which usually means the issuer or its affiliates are placing the securities directly.

Q: Where is Onex Partners V Annex I LP located?

The issuer's address on its SEC filings is 712 Fifth Avenue, 40th Floor, New York, NY 10019. Its phone number of record is (212) 582-2211. It is organized under the laws of Delaware.

AltStreetEDGAR DatabaseOnex Partners V Annex I LP
SEC filing record
Primary Source · SEC.gov
Onex Partners V Annex I LPFund Vehicle2026 vintage506(b), 3(c)(1)
Raised
Pre-open
Investors
—
Min Invest
None stated
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AltStreet Analysis
·Generated from EDGAR primary sources
Onex Partners V Annex I LP is a Delaware-domiciled pooled investment fund vehicle affiliated with the Onex Partners V fund family, with executive officer entities Onex Partners V GP LP, Onex Partners V GP Limited, and Onex Partners Manager LP. The Form D (filed 2026-11-10, original filing) claims 506(b) and 3(c)(1) exemptions with total amount sold, investor count, first sale date, and minimum investment all undisclosed, consistent with a pre-open institutional fund filing. No parent platform or sibling entities are currently matched in the AltStreet database.
This filing represents a typical institutional private equity structure within the alternative_investment category: a 506(b) offering paired with a 3(c)(1) Investment Company Act exemption, which is standard for privately placed funds limited to accredited investors and capped at 100 beneficial owners. The lack of disclosed minimum investment and raise amount is common at this pre-open stage for large PE fund vehicles, where LP commitment terms are detailed in the limited partnership agreement rather than the public Form D.
Data Flags
First Sale Date / Total Amount SoldNo first sale date or raised amount is disclosed; this is an original (non-amendment) filing in pre-open status, consistent with early-stage formation of an institutional PE vehicle rather than a reporting gap.
Entity Name'Annex I' naming suggests this is a parallel or side vehicle to a primary Onex Partners V fund, likely structured to accommodate specific investor classes (e.g., tax, regulatory, or timing considerations) rather than a standalone capital pool.
EDGAR Filing Data
Form D — Primary Source
View on SEC.gov 
CIK Number0002157588
Entity NameOnex Partners V Annex I LP
Exemption506(b), 3(c)(1)
Entity Type—
Jurisdiction of OrganizationDelaware
Issuer Address712 Fifth Avenue, 40th Floor, New York, NY 10019
Phone(212) 582-2211
Industry / Fund Type—
Securities TypeEquity, Pooled Investment Fund
First Sale Date—
Filing DateNovember 10, 2026
Accession Number0002157588-26-000001
Total Offering Amount—
Total Amount Sold—
Total Investors—
Minimum Investment$0 (no stated minimum)
Offering Duration—
State (Issuer Address)NY
Amendment CountOriginal filing only
Related Persons (Form D)
Executive officers, directors, and promoters listed on the SEC Form D filing. Source: SEC.gov.
MATTHEW MURPHY
Executive Officer, Promoter · NEW YORK, NY
N/A ONEX PARTNERS V GP LP
Executive Officer · NEW YORK, NY
N/A ONEX PARTNERS V GP LIMITED
Executive Officer · NEW YORK, NY
N/A ONEX PARTNERS MANAGER LP
Executive Officer · NEW YORK, NY
AMIR MOTAMEDI
Director · NEW YORK, NY
Questions About Onex Partners V Annex I LP
Each answer is built from the values on the SEC filing and the AltStreet ledger, not from the issuer's marketing.
What is Onex Partners V Annex I LP?Onex Partners V Annex I LP is an issuer that filed a Form D with the SEC on November 10, 2026. The filing claims 506(b), 3(c)(1).
Is Onex Partners V Annex I LP legit?AltStreet does not rate legitimacy; it reports the public record. Onex Partners V Annex I LP filed a Form D with the SEC on November 10, 2026 claiming 506(b), 3(c)(1). A Form D is a notice of an exempt offering, not a review or approval of it. AltStreet's enforcement record (SEC, FINRA and state actions) shows no action naming the issuer as of today. Before investing, confirm the filing on EDGAR, check the seller's registration on FINRA BrokerCheck, and read the offering documents, which a Form D does not include.
Is Onex Partners V Annex I LP registered with or approved by the SEC?No. A Form D is a notice that an issuer is selling securities under an exemption from registration, and the SEC does not review, approve, or pass on the merits of the offering. The filing shows that Onex Partners V Annex I LP claimed 506(b), 3(c)(1) and disclosed the items the form requires, such as the amount sold, the minimum investment, related persons, and anyone paid to sell the securities. It does not verify the issuer's claims or its business.
How much has Onex Partners V Annex I LP raised?Onex Partners V Annex I LP reported no amount sold as of the Form D filed November 10, 2026.
Who is selling Onex Partners V Annex I LP and how are they paid?The Form D names no recipient of sales compensation, which usually means the issuer or its affiliates are placing the securities directly.
Where is Onex Partners V Annex I LP located?The issuer's address on its SEC filings is 712 Fifth Avenue, 40th Floor, New York, NY 10019. Its phone number of record is (212) 582-2211. It is organized under the laws of Delaware.
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Sponsor EDGAR Footprint
Entities on EDGAR8
Total raised—
Vintages2026
Aggregated across this manager's Form D entities tracked by AltStreet. Source: SEC EDGAR.
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Data Methodology
Capital raise figures, investor counts, and filing dates are sourced directly from SEC EDGAR Form D primary documents via the SEC EDGAR submissions API and full-text search index. EDGAR entity profiles and deal-level data are reviewed by AltStreet analysts with backgrounds in corporate finance and securities law — cross-referenced against offering circulars, audited financial statements, and primary regulatory filings before publication. Platform-provided information, where present, is clearly labeled and does not affect EDGAR data or AltStreet editorial coverage. Platforms may request factual corrections for demonstrable inaccuracies by contacting [email protected]. This page does not constitute investment advice.