Butterfly Network (NYSE: BFLY) founder files 13D/A, sets 10b5-1 sale plan

Rhea-AI Filing Summary

Butterfly Network, Inc. (BFLY) received an amended Schedule 13D from founder Jonathan M. Rothberg, Ph.D., updating his ownership and disclosing a new pre-arranged trading plan for estate planning. Dr. Rothberg reports beneficial ownership of 3,548,159 shares of Class A common stock, representing 1.6% of that class as of February 19, 2026. He also reports beneficial ownership of 26,426,937 shares of Class B common stock, representing 100% of the Class B shares outstanding as of that date, primarily through several 4C Holdings entities and trusts for his children.

In connection with estate planning, Dr. Rothberg and entities owned by trusts for his children have entered into a Rule 10b5-1 trading plan. Under this plan, sales of up to 2,799,818 shares of Class A common stock and 5,000,000 shares of Class B common stock may be effected during a plan sales period beginning after the Rule 10b5-1(c) cooling-off period on July 14, 2026 and ending on July 14, 2027. Any sales under the plan are subject to specified minimum price and volume parameters, and there is no assurance that any shares will actually be sold.

Insights

Equity ownership & governance analyst

Large holder adopts 10b5-1 plan for potential share sales over one year.

Jonathan M. Rothberg discloses substantial holdings in Butterfly Network, including 3,548,159 Class A shares (1.6% of that class) and 26,426,937 Class B shares (100% of that class) as of February 19, 2026. Class B control remains concentrated through 4C Holdings entities and family trusts.

He and entities owned by trusts for his children have adopted a Rule 10b5-1 trading plan for estate planning. The plan allows sales of up to 2,799,818 Class A shares and 5,000,000 Class B shares between July 14, 2026 and July 14, 2027, subject to minimum price and volume conditions. Rule 10b5-1 plans are pre-arranged programs designed to standardize insider trading activity.

The filing does not guarantee that any shares will be sold; actual activity will depend on market conditions and the plan’s parameters. Investors relying on future disclosures in company filings can observe how many shares, if any, are ultimately sold under this plan and any resulting changes in voting power.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 9)

Butterfly Network, Inc.

(Name of Issuer)

Class A common stock, par value $0.0001 per share, Class B common stock, par value $0.0001 per share

(Title of Class of Securities)

(CUSIP Number)

Jonathan M. Rothberg, Ph.D.
c/o Butterfly Network, Inc., 1600 Distri,
Burlington, MA, 01803
(781) 557-4800

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

03/13/2026

(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).

schemaVersion:

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

Rothberg Jonathan M.

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 2,821,463.00
8	Shared Voting Power 726,696.00
9	Sole Dispositive Power 2,821,463.00
10	Shared Dispositive Power 726,696.00

11

Aggregate amount beneficially owned by each reporting person

3,548,159.00

12

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

13

Percent of class represented by amount in Row (11)

1.6 %

14

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person:

This Reporting Person's table is for Class A common stock. Rows 7, 9 and 11 consists of (i) 2,799,818 shares of Class A common stock of Butterfly Network, Inc. (f/k/a Longview Acquisition Corp.) (the "Issuer") held by Jonathan M. Rothberg, Ph.D. and (ii) stock options to purchase 21,645 shares of Class A common stock of the Issuer which are exercisable within 60 days of March 13, 2026, held by Dr. Jonathan M. Rothberg. Rows 8, 10 and 11 consists of 726,696 shares of Class A common stock of the Issuer held by Dr. Rothberg's spouse. Row 13 is calculated based on 228,205,930 shares of Class A common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

Rothberg Jonathan M.

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 26,426,937.00
8	Shared Voting Power 0.00
9	Sole Dispositive Power 26,426,937.00
10	Shared Dispositive Power 0.00

11

Aggregate amount beneficially owned by each reporting person

26,426,937.00

12

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

13

Percent of class represented by amount in Row (11)

100 %

14

Type of Reporting Person (See Instructions)

IN

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Rows 7, 9 and 11 consists of 26,426,937 shares of Class B common stock of the Issuer held by 4C Holdings I, LLC, 4C Holdings II, LLC, 4C Holdings III, LLC, 4C Holdings IV, LLC and 4C Holdings V, LLC and shares distributed from 4C Holdings I, LLC and held by entities owned by trusts created for the benefit of Dr. Jonathan Rothberg's children. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

4C Holdings I, LLC

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

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 4,716,596.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 4,716,596.00

11

Aggregate amount beneficially owned by each reporting person

4,716,596.00

12

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

13

Percent of class represented by amount in Row (11)

17.8 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

4C Holdings II, LLC

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

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 2,621,701.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 2,621,701.00

11

Aggregate amount beneficially owned by each reporting person

2,621,701.00

12

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

13

Percent of class represented by amount in Row (11)

9.9 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

4C Holdings III, LLC

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

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 2,621,701.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 2,621,701.00

11

Aggregate amount beneficially owned by each reporting person

2,621,701.00

12

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

13

Percent of class represented by amount in Row (11)

9.9 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

4C Holdings IV, LLC

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

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 2,621,701.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 2,621,701.00

11

Aggregate amount beneficially owned by each reporting person

2,621,701.00

12

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

13

Percent of class represented by amount in Row (11)

9.9 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

CUSIP No.

1

Name of reporting person

4C Holdings V, LLC

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

DELAWARE

Number of Shares Beneficially Owned by Each Reporting Person With:

7	Sole Voting Power 0.00
8	Shared Voting Power 8,845,238.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 8,845,238.00

11

Aggregate amount beneficially owned by each reporting person

8,845,238.00

12

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

13

Percent of class represented by amount in Row (11)

33.5 %

14

Type of Reporting Person (See Instructions)

OO

Comment for Type of Reporting Person:

This Reporting Person's table is for Class B common stock. Row 13 is calculated based on 26,426,937 shares of Class B common stock of the Issuer outstanding as of February 19, 2026.

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Class A common stock, par value $0.0001 per share, Class B common stock, par value $0.0001 per share
(b)	Name of Issuer: Butterfly Network, Inc.
(c)	Address of Issuer's Principal Executive Offices: 1600 District Avenue, Burlington, MASSACHUSETTS , 01803.
Item 1 Comment: Explanatory Note This Amendment No. 9 to Schedule 13D ("Amendment No. 9") amends and supplements the Schedule 13D filed on February 22, 2021, as amended by Amendment No. 1 filed on March 26, 2021, Amendment No. 2 filed on March 28, 2022, Amendment No. 3 filed on September 16, 2022, Amendment No. 4 filed on September 13, 2023, Amendment No. 5 filed on August 30, 2024, Amendment No. 6 filed on March 7, 2025, Amendment No. 7 filed on December 1, 2025 and Amendment No. 8 filed on December 17, 2025 (as amended, the "Schedule 13D") relating to the Class A common stock, par value $0.0001 per share, and Class B common stock, par value $0.0001 per share, of Butterfly Network, Inc. (f/k/a Longview Acquisition Corp.), a Delaware corporation (the "Issuer"). Information reported in the Schedule 13D remains in effect except to the extent that it is amended, restated or superseded by information contained in this Amendment No. 9. Capitalized terms used but not defined herein have the meanings ascribed to them in the Schedule 13D.
Item 4.	Purpose of Transaction
	Item 4 of the Schedule 13D is hereby amended and supplemented by adding the following: In connection with estate planning, Dr. Rothberg and entities owned by trusts created for the benefit of Dr. Rothberg's children have entered into a trading plan pursuant to Rule 10b5-1 under the Securities Exchange Act of 1934, as amended (the "Plan"), a copy of which is attached hereto as Exhibit 6. Pursuant to the Plan, sales of up to 2,799,818 shares of Class A common stock and 5,000,000 shares of Class B common stock may be effected during the plan sales period beginning following the cooling-off period contained in Rule 10b5-1(c) on July 14, 2026 and ending on July 14, 2027 in accordance with the terms and conditions of the Plan. The sale of shares of Class A common stock and Class B common stock under the Plan is subject to minimum price and volume parameters included in the Plan, and there is no assurance that any shares of Class A common stock or Class B common stock will be sold under the Plan.
Item 7.	Material to be Filed as Exhibits.
	Item 7 of the Schedule 13D is hereby amended by adding the following exhibit: Exhibit No. 6 - Rule 10b5-1 Trading Plan

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.

Rothberg Jonathan M.

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D.
Date:	03/17/2026

Rothberg Jonathan M.

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D.
Date:	03/17/2026

4C Holdings I, LLC

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D., Manager
Date:	03/17/2026

4C Holdings II, LLC

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D., Manager
Date:	03/17/2026

4C Holdings III, LLC

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D., Manager
Date:	03/17/2026

4C Holdings IV, LLC

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D., Manager
Date:	03/17/2026

4C Holdings V, LLC

Signature:	/s/ Jonathan M. Rothberg
Name/Title:	Jonathan M. Rothberg, Ph.D., Manager
Date:	03/17/2026

FAQ

How many Butterfly Network (BFLY) Class A shares does Jonathan Rothberg beneficially own?

Jonathan Rothberg reports beneficial ownership of 3,548,159 shares of Butterfly Network Class A common stock, representing 1.6% of that class as of February 19, 2026. This total includes personally held shares, exercisable stock options, and shares held by his spouse.

What is Jonathan Rothberg’s ownership of Butterfly Network (BFLY) Class B shares?

Rothberg reports beneficial ownership of 26,426,937 Butterfly Network Class B common shares, representing 100% of that class as of February 19, 2026. These shares are held through multiple 4C Holdings LLC entities and entities owned by trusts created for the benefit of his children.

What does the new Rule 10b5-1 trading plan for Butterfly Network (BFLY) shares allow?

The Rule 10b5-1 plan allows potential sales of up to 2,799,818 Class A shares and 5,000,000 Class B shares. Sales may occur between July 14, 2026 and July 14, 2027, subject to specified minimum price and volume parameters defined in the plan’s terms.

When will sales under Jonathan Rothberg’s Butterfly Network (BFLY) 10b5-1 plan occur?

The plan’s sales period begins after the Rule 10b5-1(c) cooling-off period on July 14, 2026 and ends on July 14, 2027. Any actual share sales must also satisfy the minimum price and trading volume conditions set in the plan.

Is Butterfly Network (BFLY) guaranteed to see insider share sales under this 10b5-1 plan?

No. The filing explicitly states there is no assurance that any Class A or Class B shares will be sold under the plan. Executions depend on meeting minimum price and volume thresholds and prevailing market conditions during the plan period.

Why did Jonathan Rothberg adopt the Butterfly Network (BFLY) 10b5-1 trading plan?

The filing explains that Rothberg and entities owned by trusts for his children adopted the Rule 10b5-1 trading plan in connection with estate planning. Such plans can help systematically diversify or transfer holdings while following predefined trading instructions.