Key facts
- This page summarizes Shan Riku Sakakibara's Form 4 filing for BillionToOne, Inc. (BLLN).
- 13 reported transactions and 4 derivative rows are listed below.
- Accepted by SEC: 13 Jul 2026, 16:39.
Shan Riku Sakakibara - 09 Jul 2026 Form 4 Insider Report for BillionToOne, Inc. (BLLN)
- Reporting relationship
- Chief Product Officer
- Issuer ticker
- BLLN
- Reported as of
- 09 Jul 2026
- Net transaction value
- -$1,000,000
- SEC form
- 4
- Accepted by SEC
- 13 Jul 2026, 16:39:18 UTC
- Prior SEC filing
- 26 Jun 2026
- Next SEC filing
- 04 Aug 2026
- Source filing
- View source filing
- Reporting owner signature
- /s/ Thomas P. Lynch, Attorney-in-Fact
Source evidence
Original filing metadata and source links for verification.
5 source fields
Reporting owner
1 detail
Filing notes and source
Key filing fact
Shan Riku Sakakibara filed Form 4 for BillionToOne, Inc. (BLLN) on 13 Jul 2026.
Change
- Previous filing in this sequence was filed on 26 Jun 2026.
- Current net transaction value: -$1,000,000.
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
Filed on Form 4
View source filing
Ownership activity is grounded in SEC Form 4 disclosures.
Reporting Owners (1)
CIK 0002088547
Primary reporting owner
Sakakibara Shan Riku
- Relationship
- Chief Product Officer
- Address
- C/O BILLIONTOONE, INC., 1035 O'BRIEN DRIVE, MENLO PARK
- Signature
- /s/ Thomas P. Lynch, Attorney-in-Fact
- Signature date
- 13 Jul 2026
Reported non-derivative transactions
Shares, units, or other non-derivative securities reported in this filing.
BLLN
transaction
Class A Common Stock
Options Exercise
- Transaction value
- Shares
- +174
- Change %
- +0.08%
- Price
- $8.65*
- Shares after
- 208,174
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Options Exercise
- Transaction value
- Shares
- +1,117
- Change %
- +0.54%
- Price
- $30.78*
- Shares after
- 209,291
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Options Exercise
- Transaction value
- Shares
- +1,355
- Change %
- +0.65%
- Price
- $30.78*
- Shares after
- 210,646
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Options Exercise
- Transaction value
- Shares
- +1,354
- Change %
- +0.64%
- Price
- $30.78*
- Shares after
- 212,000
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Sale
- Transaction value
- $500,000
- Shares
- -4,000
- Change %
- -1.9%
- Price
- $125.00
- Shares after
- 208,000
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Sale
- Transaction value
- $21,750
- Shares
- -174
- Change %
- -0.08%
- Price
- $125.00
- Shares after
- 207,826
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Sale
- Transaction value
- $139,625
- Shares
- -1,117
- Change %
- -0.54%
- Price
- $125.00
- Shares after
- 206,709
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Sale
- Transaction value
- $169,375
- Shares
- -1,355
- Change %
- -0.66%
- Price
- $125.00
- Shares after
- 205,354
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
BLLN
transaction
Class A Common Stock
Sale
- Transaction value
- $169,250
- Shares
- -1,354
- Change %
- -0.66%
- Price
- $125.00
- Shares after
- 204,000
- Date
- 09 Jul 2026
- Ownership
- Direct
- Footnotes
- F1
Reported derivative securities
Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.
BLLN
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -174
- Change %
- -0.48%
- Price
- $8.65*
- Shares after
- 35,826
- Date
- 09 Jul 2026
- Ownership
- Direct
- Underlying class
- Class A Common Stock
- Underlying amount
- 174
- Exercise price
- $8.65
- Footnotes
- F2
BLLN
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -1,117
- Change %
- -1.7%
- Price
- $30.78*
- Shares after
- 63,883
- Date
- 09 Jul 2026
- Ownership
- Direct
- Underlying class
- Class A Common Stock
- Underlying amount
- 1,117
- Exercise price
- $30.78
- Footnotes
- F2
BLLN
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -1,355
- Change %
- -2.1%
- Price
- $30.78*
- Shares after
- 62,528
- Date
- 09 Jul 2026
- Ownership
- Direct
- Underlying class
- Class A Common Stock
- Underlying amount
- 1,355
- Exercise price
- $30.78
- Footnotes
- F2
BLLN
transaction
Derivative
Stock Option (right to buy)
Options Exercise
- Transaction value
- Shares
- -1,354
- Change %
- -2.2%
- Price
- $30.78*
- Shares after
- 61,174
- Date
- 09 Jul 2026
- Ownership
- Direct
- Underlying class
- Class A Common Stock
- Underlying amount
- 1,354
- Exercise price
- $30.78
- Footnotes
- F2
* marks a reported price that did not pass the local price check.
Additional SEC filing notes
Filing notes and footnotes
Rule 10b5-1 trading plan
These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.
Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).
Explanation of responses 2 footnotes
Footnote F1
The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on March 6, 2026.
Footnote F2
The options are fully vested and exercisable. The terms of the underlying option grant are as previously reported on the Reporting Person's Form 3 filed on November 5, 2025.