Bipul Sinha Files 13D/A for Rubrik: 13.8M Shares, Recent Sale and Gift

Rhea-AI Filing Summary

Bipul Sinha filed Amendment No. 1 to a Schedule 13D for Rubrik, Inc. (Class A common stock). The filing states the Reporting Person beneficially owns 13,791,466 shares, representing 8.9% of the Class A shares based on 142,085,609 shares outstanding as of August 31, 2025. That total includes 2,499,975 shares issuable within 60 days upon exercise of stock options. The amendment discloses two transactions on September 12, 2025: a sale of 615,807 shares and a gift of 150,000 shares. Other reported cover-page powers show sole voting and dispositive power over the 13,791,466 shares. The filing otherwise states no additional changes to the original Schedule 13D.

Positive

• Full disclosure of beneficial ownership at 13,791,466 shares (8.9%) provides transparency for investors
• Reports exercisable options (2,499,975 shares exercisable within 60 days), clarifying potential near-term ownership changes
• Documents recent transactions (sale and gift) so market participants can see changes in holdings

Negative

• Reporting Person sold 615,807 shares on September 12, 2025, which reduces the economic stake
• Reporting Person gifted 150,000 shares on September 12, 2025, further transferring ownership

Insights

Financial Analyst

TL;DR: Beneficial ownership at 8.9% including exercisable options; recent sale and gift reduce economic stake but overall position remains material.

The Reporting Person holds a significant minority position in Rubrik with 13,791,466 shares (8.9%), and the position includes nearly 2.5 million option-backed shares exercisable within 60 days, which increases near-term potential ownership dilution or control dynamics. The disclosed sale of 615,807 shares and gift of 150,000 shares on the same date are notable liquidity and transfer events but do not, per the filing, eliminate the Reporting Person's material stake. For investors, the combination of sizeable current ownership plus exercisable options means the Reporting Person continues to be an influential holder; however, the sale indicates partial monetization or reallocation of holdings.

Corporate Governance Expert

TL;DR: Schedule 13D amendment confirms material insider stake and recent transfers; governance implications are neutral without further context.

The amendment clarifies that the Reporting Person retains sole voting and dispositive power over the reported shares, which preserves influence on corporate matters. The inclusion of exercisable options is important for assessing future voting capacity. The gift and sale are disclosed as required but the filing contains no statements about changes in intent, group formation, or plans affecting corporate control. Absent additional agreements or group affiliations, the filing signals continued material ownership with routine transfers rather than an expressed change in strategy.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

RUBRIK, INC.

(Name of Issuer)

Class A Common Stock

(Title of Class of Securities)

781154109

(CUSIP Number)

Anne-Kathrin Lalendran
c/o Rubrik Inc., 3495 Deer Creek Road
Palo Alto, CA, 94304
884-478-2745

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications)

09/12/2025

(Date of Event Which Requires Filing of This Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§ 240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box.

The information required on the remainder of this cover page shall not be deemed to be "filed" for the purpose of Section 18 of the Securities Exchange Act of 1934 ("Act") or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

SCHEDULE 13D

CUSIP No. 781154109

1

Name of reporting person

Bipul Sinha

2

Check the appropriate box if a member of a Group (See Instructions)

(a)
(b)

3

SEC use only

4

Source of funds (See Instructions)

PF

5

Check if disclosure of legal proceedings is required pursuant to Items 2(d) or 2(e)

6

Citizenship or place of organization

UNITED STATES

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 13,791,466.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 13,791,466.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

13,791,466.00

12

Check if the aggregate amount in Row (11) excludes certain shares (See Instructions)

13

Percent of class represented by amount in Row (11)

8.9 %

14

Type of Reporting Person (See Instructions)

IN

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Class A Common Stock
(b)	Name of Issuer: RUBRIK, INC.
(c)	Address of Issuer's Principal Executive Offices: 3495 Deer Creek Road, Palo Alto, CALIFORNIA , 94304.
Item 1 Comment: This Amendment No. 1 ("Amendment No. 1") to Schedule 13D relates to the shares of Class A common stock, $0.00001 par value per share (the "Class A Common Stock"), of Rubrik, Inc., a Delaware corporation (the "Issuer"), and amends and supplements the initial statement on Schedule 13D filed by Bipul Sinha (the "Reporting Person") with the Securities and Exchange Commission on April 1, 2025, Unless otherwise defined herein, capitalized terms used in this Amendment No. 1 shall have the meanings ascribed to them in the Schedule 13D. Unless amended or supplemented below, the information in the Schedule 13D remains unchanged.
Item 5.	Interest in Securities of the Issuer
(a)	Rows 11 and 13 of the Reporting Person's cover page to this Schedule 13D set forth the aggregate number of shares of Class A Common Stock and percentages of the shares of Class A Common Stock beneficially owned by the Reporting Person and are incorporated herein by referenced. The percentage set forth in row 13 is based upon 142,085,609 shares of the Issuer's Class A Common Stock outstanding as of August 31, 2025, as reported in the Issuer's Form 10-Q filed the SEC on September 10, 2025. The Reporting Person's ownership of the Issuer's securities includes 2,499,975 shares issuable within 60 days of the date of this report, upon the exercise of stock options held by the Reporting Person.
(b)	Rows 7 through 10 of the Reporting Person's cover page to this Schedule 13D set forth the number of shares of Class A Common Stock as to which such Reporting Person has the sole or shared power to vote or direct the vote and sole or shared power to dispose or to direct the disposition and are incorporated by reference.
(c)	Except as set forth below, the Reporting Person has not effected any transactions in the Class A Common Stock during the past sixty days: Sale of Class A Common Stock: On September 12, 2025, the Reporting Person sold 615,807 shares of the Issuer's Class A Common Stock. Gift of Shares: On September 12, 2025, the Reporting Person gifted 150,000 shares of the Issuer's Class A Common Stock.
(d)	Not applicable.
(e)	Not applicable.

SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Bipul Sinha

Signature:	/s/ Bipul Sinha
Name/Title:	Bipul Sinha
Date:	09/12/2025

FAQ

How many Rubrik (RBRK) Class A shares does Bipul Sinha beneficially own?

The filing states 13,791,466 shares, representing 8.9% of Class A common stock based on 142,085,609 shares outstanding.

Does the Schedule 13D/A report any stock options for Bipul Sinha?

Yes. The ownership includes 2,499,975 shares issuable within 60 days upon exercise of stock options.

Were there any recent transactions disclosed by the Reporting Person?

Yes. On September 12, 2025, the Reporting Person sold 615,807 shares and gifted 150,000 shares of Class A common stock.

Does the filer share voting or dispositive power over the reported shares?

No. The cover page reports sole voting power and sole dispositive power for the 13,791,466 shares and 0 shared power.

What is the source of funds reported for the acquisition?

The filing lists the source of funds as PF (private funds), as shown on the cover page.