Dr. Avi S. Katz - 03 Oct 2025 Form 3 Insider Report for GigCapital8 Corp. (GIW)

Reporting relationship: Chief Executive Officer, Director, 10%+ Owner
Issuer ticker: GIW
Reported as of: 03 Oct 2025
Net transaction value: $0
SEC form: 3
Accepted by SEC: 07 Oct 2025, 21:02:57 UTC
Prior SEC filing: 02 Sep 2025
Next SEC filing: 17 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Dr. Avi S. Katz, individually

Key filing fact

Dr. Avi S. Katz filed Form 3 for GigCapital8 Corp. (GIW) on 07 Oct 2025.

Key facts

This page summarizes Dr. Avi S. Katz's Form 3 filing for GigCapital8 Corp. (GIW).
0 reported transactions and 2 derivative rows are listed below.
Accepted by SEC: 07 Oct 2025, 21:02.

Change

Previous filing in this sequence was filed on 02 Sep 2025.
Current net transaction value: $0.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Official SEC source

Ownership activity is grounded in SEC Form 3 disclosures.

View source filing

Reporting Owners (3)

CIK 0001451693 Primary reporting owner

Katz Avi S

Relationship: Chief Executive Officer, Director, 10%+ Owner
Address: C/O GIGCAPITAL8 CORP., 1731 EMBARCADERO ROAD, SUITE 200, PALO ALTO
Signature: /s/ Dr. Avi S. Katz, individually
Signature date: 07 Oct 2025

CIK 0002080021

GigAcquisitions8 Corp.

Relationship: 10%+ Owner
Address: C/O GIGCAPITAL8 CORP., 1731 EMBARCADERO RD., SUITE 200, PALO ALTO
Signature: /s/ Dr. Avi S. Katz, as managing member of GigAcquisitions8 Corp.
Signature date: 07 Oct 2025

CIK 0001430575

Dinu Raluca

Relationship: Director
Address: C/O GIGCAPITAL8 CORP., 1731 EMBARCADERO RD., SUITE 200, PALO ALTO
Signature: /s/ D. Raluca Dinu
Signature date: 07 Oct 2025

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

GIW holding

Class A ordinary shares

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 10,000
Date: 03 Oct 2025
Ownership: By GigAcquisitions8 Corp.
Footnotes: F1, F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

GIW holding Derivative

Class B ordinary shares

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after
Date: 03 Oct 2025
Ownership: By GigAcquisitions8 Corp.
Underlying class: Class A ordinary shares
Underlying amount: 6,053,167
Exercise price
Footnotes: F2, F3, F4

GIW holding Derivative

Rights

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after
Date: 03 Oct 2025
Ownership: By GigAcquisitions8 Corp.
Underlying class: Class A ordinary shares
Underlying amount: 2,000
Exercise price
Footnotes: F2, F5

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Explanation of responses 5 footnotes

Footnote F1

Includes 10,000 Class A ordinary shares underlying the private placement units purchased concurrently with the initial public offering.

Footnote F2

The Class B ordinary shares and Class A ordinary shares underlying the private placement units are held directly by GigAcquisitions8 Corp. (the "Sponsor"). The shares held by the Sponsor are beneficially owned equally (50% each) by Dr. Katz, the Issuer's Chief Executive Officer and Chairman of the Board of Directors, and Dr. Raluca Dinu, the Issuer's Director. Dr. Katz and Dr. Dinu are the members of the Sponsor, who both have the voting and dispositive power over the shares held by the Sponsor.

Footnote F3

The Class B ordinary shares are convertible for the Issuer's Class A ordinary shares as described under the heading "Description of Securities" in the Issuer's Registration Statement on Form S-1 (File No. 333-289479) and have no expiration date.

Footnote F4

Includes 6,053,167 Class B ordinary shares of the Issuer acquired by GigAcquisitions8 Corp. (the "Sponsor") prior to the Issuer's initial public offering convertible for the Issuer's Class A ordinary shares. As a result of the underwriter's full exercise of its over-allotment option to purchase 3,300,000 units on October 7, 2025, no such shares are subject to forfeiture.

Footnote F5

Includes 10,000 rights underlying the private placement units, which were sold in a private placement taking place simultaneously with the Issuer's initial public offering. Each right is exchangeable for one-fifth of one Class A ordinary share upon the completion of the Issuer's initial business combination.