BillionToOne, Inc. (BLLN) SVP sells 14,199 shares via Rule 10b5-1 plan

Rhea-AI Filing Summary

BillionToOne, Inc. executive Nancy JoAnn Johnson, Senior Vice President of Sales and Commercial Operations, reported selling an aggregate 14,199 shares of Class A Common Stock on July 16, 2026. The four open-market or private transactions, executed under a Rule 10b5-1 trading plan adopted on March 6, 2026, were completed at weighted average prices between approximately $126.330 and $130.010 per share.

Insider Trade Summary 10b5-1

Net Seller: 14,199 shares

Net Sell 4 txns

Insider Johnson Nancy JoAnn

Role See Remarks

Sold 14,199 shs ($1.82M)

Type	Security	Shares	Price	Value
Sale	Class A Common Stock F1, F2	2,133	$126.9821	$271K
Sale	Class A Common Stock F1, F3	5,559	$127.886	$711K
Sale	Class A Common Stock F1, F4	5,601	$128.9551	$722K
Sale	Class A Common Stock F1, F5	906	$129.7787	$118K

Holdings After Transaction: Class A Common Stock — 6,900 shares (Direct)

Footnotes (5)

1. 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.
2. F2. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $126.330 to $127.300 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
3. F3. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $127.445 to $128.430 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
4. F4. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.475 to $129.340 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.
5. F5. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $129.580 to $130.010 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Key Figures

Total shares sold: 14199 shares First transaction size and price: 2133.0000 shares at $126.9821 per share Second transaction size and price: 5559.0000 shares at $127.8860 per share +4 more

7 metrics

Total shares sold 14199 shares Aggregate Class A Common Stock sold by Nancy JoAnn Johnson on July 16, 2026

First transaction size and price 2133.0000 shares at $126.9821 per share Class A Common Stock sale on July 16, 2026

Second transaction size and price 5559.0000 shares at $127.8860 per share Class A Common Stock sale on July 16, 2026

Third transaction size and price 5601.0000 shares at $128.9551 per share Class A Common Stock sale on July 16, 2026

Fourth transaction size and price 906.0000 shares at $129.7787 per share Class A Common Stock sale on July 16, 2026

Overall trade price range $126.330–$130.010 per share Ranges from all weighted average price footnotes for July 16, 2026 sales

Rule 10b5-1 plan adoption date March 6, 2026 Adoption date of Johnson’s Rule 10b5-1 trading plan covering these transactions

Key Terms

Rule 10b5-1 trading plan, weighted average price, Class A Common Stock, open market or private transaction

4 terms

Rule 10b5-1 trading plan regulatory

"transactions were effected pursuant to a Rule 10b5-1 trading plan adopted"

A Rule 10b5-1 trading plan is a pre-arranged schedule that allows company insiders to buy or sell stock at specific times, even if they have inside information. It helps prevent accusations of unfair trading by making these transactions look planned and transparent, rather than sneaky or illegal.

weighted average price financial

"The reported price in Column 4 is a weighted average price."

Weighted average price is the average price of a security where each trade or component is counted according to its size, so bigger trades pull the average more than smaller ones. Think of it like calculating the average cost of a grocery haul where items you bought more of have greater influence on the final per-item cost. Investors use it to understand the true average price paid or received, judge execution quality, and compare trading performance against market movement.

Class A Common Stock financial

"security_title": "Class A Common Stock""

Class A common stock is a category of a company’s shares that carries a specific set of ownership rights—most commonly defined voting power and claims on dividends—set out in the company’s charter. For investors it matters because the class determines how much influence you have over corporate decisions, the share’s likely dividend and trading behavior, and how it compares in value to other share classes, like choosing a particular seat with different privileges at the company’s decision-making table.

open market or private transaction financial

"Sale in open market or private transaction"

AI-generated analysis. How Rhea-AI works. Not financial advice.

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Form 4 Insider Transactions: What Each Field Means →

Available on EDGAR 07/20/2026 - 07:38 PM Accepted by SEC EDGAR 07/20/2026 - 07:38 PM Learn about SEC filing dates

FAQ

What insider stock transaction did BillionToOne (BLLN) report for Nancy JoAnn Johnson?

Nancy JoAnn Johnson sold a total of 14,199 shares of BillionToOne Class A Common Stock on July 16, 2026. The sales occurred in four open-market or private transactions at weighted average prices from $126.9821 to $129.7787 per share under a Rule 10b5-1 plan.

Were the BillionToOne (BLLN) insider sales made under a Rule 10b5-1 trading plan?

Yes. The company reports the transactions were effected pursuant to a Rule 10b5-1 trading plan adopted by Nancy JoAnn Johnson on March 6, 2026. This plan pre-arranged the sales, and the filing also affirms use of a Rule 10b5-1 plan at the form level.

How many BillionToOne (BLLN) shares were sold in each reported transaction?

On July 16, 2026, Johnson sold 2,133, 5,559, 5,601, and 906 shares of BillionToOne Class A Common Stock in four separate transactions. Each transaction is reported with its own weighted average sale price and related pricing range in the accompanying footnotes.

What price ranges applied to the BillionToOne (BLLN) insider sales on July 16, 2026?

The weighted average prices reflect multiple trades in ranges of $126.330–$127.300, $127.445–$128.430, $128.475–$129.340, and $129.580–$130.010 per share. Johnson undertakes to provide full breakdowns of shares sold at each separate price upon written request.

What is Nancy JoAnn Johnson’s role at BillionToOne (BLLN)?

Nancy JoAnn Johnson is reported as an officer of BillionToOne, serving as Senior Vice President of Sales and Commercial Operations. Her position is specified in the remarks section, and she is not listed as a director or a ten percent owner in this insider report.

How many total BillionToOne (BLLN) shares did the insider sell according to this report?

Across all reported transactions, Johnson sold 14,199 shares of BillionToOne Class A Common Stock. This total is derived from the filing’s transaction summary, which aggregates the four sale entries reported for July 16, 2026, and classifies the net activity as a net-sell position.

SEC Form 4

FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934
or Section 30(h) of the Investment Company Act of 1940

OMB APPROVAL

OMB Number:			3235-0287
Estimated average burden
hours per response:			0.5

Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

X

Check this box to indicate that a transaction was made pursuant to a contract, instruction or written plan for the purchase or sale of equity securities of the issuer that is intended to satisfy the affirmative defense conditions of Rule 10b5-1(c). See Instruction 10.

1. Name and Address of Reporting Person^*

Johnson Nancy JoAnn

(Last) (First) (Middle)

C/O BILLIONTOONE, INC.

1035 O'BRIEN DRIVE

(Street)

MENLO PARK CALIFORNIA 94025

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
BillionToOne, Inc. [ BLLN ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	See Remarks

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
07/16/2026

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	Form filed by More than One Reporting Person

4. If Amendment, Date of Original Filed (Month/Day/Year)

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Class A Common Stock	07/16/2026		S(1)		2,133	D	$126.9821(2)	18,966	D
Class A Common Stock	07/16/2026		S(1)		5,559	D	$127.886(3)	13,407	D
Class A Common Stock	07/16/2026		S(1)		5,601	D	$128.9551(4)	7,806	D
Class A Common Stock	07/16/2026		S(1)		906	D	$129.7787(5)	6,900	D

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned (e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security (Instr. 3)	2. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares

Explanation of Responses:

1. 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.

2. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $126.330 to $127.300 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

3. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $127.445 to $128.430 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

4. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $128.475 to $129.340 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

5. The reported price in Column 4 is a weighted average price. These shares were sold in multiple transactions at prices ranging from $129.580 to $130.010 per share, inclusive. The holder undertakes to provide, upon written request, full information regarding the number of shares sold at each separate price within the range set forth in this footnote.

Remarks:

Senior Vice President of Sales and Commercial Operations

	/s/ Thomas P. Lynch, Attorney-in-Fact	07/20/2026
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed. If space is insufficient, see Instruction 6 for procedure.
Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB Number.
* Form 4: SEC 1474 (03-26)