Skip to content
Baker Capital StrategiesMARKETS. FILINGS. PERSPECTIVE.
Powered by THEMA

BAKER CAPITAL STRATEGIES

Get the free weekly BCS email.

Selected company filings and market updates, delivered by email. Your first report will follow soon.

  • Your weekly BCS reportMarket updates and links to filings you can explore.
  • THEMA at launchWe’ll send directions for setting up your filing alerts when THEMA officially opens.

One signup for the weekly email and your free THEMA Basic account at launch.

Already registered or a CSW member?Log in to THEMA →

At least 8 characters. This also creates your free THEMA account for launch.

You’re signing up for the weekly BCS email and THEMA launch/setup updates. Unsubscribe using the link in any email. Privacy policy · Terms

BCS

Initial Beneficial Ownership · 3

Rainier Acquisition Corporation

RNAQNASDAQEQUITYCurrent

Initial Beneficial Ownership

Filed Sep 8, 2026Accepted Sep 8, 2026, 3:58 PM EDTFiling CIK 2147219Accession 0000921895-26-002500
Share

Structured filing — 3

form309729rnaq_09082026.xml

Open full document ↗

Filing details

Report period
2026-08-27
Issuer
Rainier Acquisition Corp
Issuer CIK
0002147219
Trading symbol
RNAQ

Reporting owner 1

Name
683 Capital Management, LLC
Reporting owner CIK
0001404574
Relationship
10% owner
Address
1700 BROADWAY, SUITE 4200, NEW YORK, NY, 10019

Reporting owner 2

Name
683 Capital Partners, LP
Reporting owner CIK
0001380126
Relationship
10% owner
Address
C/O 683 CAPITAL GP, LLC, 1700 BROADWAY, SUITE 4200, NEW YORK, NY, 10019

Reporting owner 3

Name
Zweiman Ari
Reporting owner CIK
0001612431
Relationship
10% owner
Address
C/O 683 CAPITAL MANAGEMENT, 1700 BROADWAY, SUITE 4200, NEW YORK, NY, 10019

Non-derivative holdings

Non-derivative holdings · 1 reported row
SecurityAmount ownedOwnershipNature of ownership
Class A Ordinary Shares, $0.0001 Par Value862,500I[F1][F2]By 683 Capital Partners, LP
Table key
I
Indirect

Derivative holdings

Derivative holdings · 1 reported row
SecurityConversion / exercise priceExercisableExpiresUnderlying securityUnderlying sharesOwnershipNature of ownership
Redeemable warrants11.50[F4][F5][F3][F3]Class A Ordinary Shares215,625I[F1][F2]By 683 Capital Partners, LP
Table key
I
Indirect

Footnotes

F1
This Form 3 is filed jointly by 683 Capital Management, LLC ("683 Management"), 683 Capital Partners, LP ("683 Partners") and Ari Zweiman (collectively, the "Reporting Persons"). Each of the Reporting Persons may be deemed to be a member of a Section 13(d) group that collectively owns more than 10% of the Class A Ordinary Shares, $0.0001 par value per share, of Rainier Acquisition Corporation (the "Issuer"). Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein except to the extent of his or its pecuniary interest therein.↩ 1↩ 2
F2
Represents securities held directly by 683 Partners. 683 Management is the investment manager of 683 Partners. Ari Zweiman is the Managing Member of 683 Management. As a result, each of 683 Management and Ari Zweiman may be deemed to beneficially own the securities held by 683 Partners.↩ 1↩ 2
F3
Each warrant will become exercisable on the later of (i) one year following the Issuer's initial public offering and (ii) the completion by the Issuer of any merger, share exchange, asset acquisition, share purchase, reorganization or similar business combination, involving the Issuer and one or more businesses (a "Business Combination"), and expire five years after the completion of the initial Business Combination, or earlier upon redemption or liquidation.↩ 1↩ 2
F4
Exercise price is subject to adjustment in accordance with its terms.↩ 1
F5
The reported securities are included within 862,500 Units of the Issuer purchased by the Reporting Persons at $10.00 per Unit. Each Unit consists of one Class A ordinary share, $0.0001 par value per share, and one-quarter of one redeemable warrant, each whole warrant exercisable for one Class A ordinary share at an exercise price of $11.50 per share, subject to adjustment.↩ 1

Signature 1

Signed
683 CAPITAL MANAGEMENT, LLC; By: /s/ Ari Zweiman, Managing Member
Date
2026-09-08

Signature 2

Signed
683 CAPITAL PARTNERS, LP; By: 683 Capital GP, LLC General Partner; By: /s/ Ari Zweiman, Managing Member
Date
2026-09-08

Signature 3

Signed
/s/ Ari Zweiman
Date
2026-09-08

Company context

We are a blank check company incorporated on February 2, 2023 as a Cayman Islands exempted company. We are incorporated for the purpose of effecting a merger, amalgamation, share exchange, asset acquisition, share purchase, reorganization or similar business combination with one or more businesses, which we refer to throughout this prospectus as our initial business combination. We seek to partner with companies that can benefit from our scientific, investing, operating, capital markets, governance, and public-company leadership experience, and we seek to support long-term value creation through our experience, relationships, and access to capital. To date, our efforts have been limited to organizational activities as well as activities related to this offering. We have not selected any specific business combination target and we have not, nor has anyone on our behalf, initiated any substantive discussions, directly or indirectly, with any business combination target. We have generated no operating revenues to date, and we do not expect that we will generate operating revenues until we consummate our initial business combination.

Current securities

Recent company filings

  1. SCHEDULE 13G - filed by Sio Capital Management, LLC regarding Rainier Acquisition CorpNov 3, 2026
  2. Other EventsSep 11, 2026
  3. Unregistered Sales of Equity Securities · Other EventsSep 3, 2026
  4. Entry into a Material Definitive Agreement · Unregistered Sales of Equity Securities · Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements · Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year · Other EventsAug 28, 2026
  5. 424B4 filingAug 27, 2026

Privacy choices

BCS measures page use with Google Analytics using regional consent settings. You can change your preference here. Charts and market data remain available.

Essential functions — always available. Security, navigation, registration and remembering these choices.

Audience analytics

Analytics cookies are off by default for visitors Google identifies in the EEA, UK or Switzerland until allowed. Limited measurement without analytics cookies may still occur under those regional defaults.

TradingView charts, quotes and the economic calendar load automatically as page content. TradingView receives network and browser information and may collect its own usage analytics. This choice controls BCS’s Google Analytics only.

Google advertising is not enabled. Direct sponsor links do not load advertising trackers on BCS.

Turning analytics off stops future Google Analytics activity here. It does not erase information already received by the provider. Read the privacy policy.