Atlas Venture funds (QTTB) join Q32 Bio $5M PIPE deal

Rhea-AI Filing Summary

Q32 Bio Inc. received new investment from several Atlas Venture funds, which filed Amendment No. 1 to their Schedule 13D to update ownership details. Atlas Venture Opportunity Fund III bought 625,000 shares of common stock at $8.00 per share in a 2026 private placement (PIPE), for a total of $5 million.

After this transaction, the Atlas reporting entities collectively beneficially own 2,717,106 shares of Q32 Bio common stock, or about 11.5% of the 23,681,415 shares outstanding as of May 28, 2026. The PIPE added 6,725,000 shares to the prior 16,956,415 shares outstanding. Q32 Bio also agreed to a registration rights agreement, requiring it to file and have declared effective a registration statement covering the resale of PIPE shares and shares issuable from pre-funded warrants within a set timeframe.

Key Figures

PIPE purchase: 625,000 shares at $8.00/share PIPE investment size: $5 million PIPE shares issued: 6,725,000 shares +5 more

8 metrics

PIPE purchase 625,000 shares at $8.00/share AVOF III common stock bought in 2026 PIPE

PIPE investment size $5 million Aggregate purchase price paid by AVOF III

PIPE shares issued 6,725,000 shares Shares of common stock sold in 2026 PIPE

Shares outstanding 23,681,415 shares Common stock outstanding as of May 28, 2026

Atlas aggregate holdings 2,717,106 shares Collective beneficial ownership of Reporting Persons

Ownership percentage 11.5% Estimated share of Q32 Bio common stock held collectively

Fund X ownership 3.6% Percent of class held by Fund X Reporting Persons

Opportunity Fund III ownership 2.6% Percent of class held by Opportunity Fund III Reporting Persons

Key Terms

Schedule 13D, securities purchase agreement, pre-funded warrants, private placement, +2 more

6 terms

Schedule 13D regulatory

"This Amendment No. 1 to ("Amendment No. 1") is being filed as an amendment to the statement on relating to common stock"

A Schedule 13D is a legal document that investors file with regulators when they buy a large enough stake in a company to potentially influence its management or decisions. It provides details about the investor’s intention, ownership stake, and plans, helping other investors understand who is gaining control and what their motives might be.

securities purchase agreement financial

"the Issuer entered into a securities purchase agreement with a number of institutional investors (the "2026 PIPE Investors")"

A securities purchase agreement is a written contract between a buyer and a seller outlining the terms for buying or selling financial assets such as stocks or bonds. It specifies details like the price, quantity, and conditions of the transaction, similar to a shopping list with agreed-upon terms. For investors, it provides clarity and legal protection when transferring ownership of these financial instruments.

pre-funded warrants financial

"the Issuer agreed to issue and sell shares of common stock and pre-funded warrants in a private placement (the "2026 PIPE")"

Pre-funded warrants are financial instruments that give investors the right to purchase a company's stock at a set price, but with most or all of the purchase price paid upfront. They function like a coupon or gift card for stock, allowing investors to buy shares later at a fixed price, which can be beneficial if they want to avoid future price increases. This makes them important for investors seeking flexibility and certainty in their investment plans.

private placement financial

"issue and sell shares of common stock and pre-funded warrants in a private placement (the "2026 PIPE")"

A private placement is a way for companies to raise money by selling securities directly to a small group of investors instead of through a public offering. This process is often quicker and less regulated, making it similar to offering a special, exclusive investment opportunity to select individuals or institutions. For investors, it can provide access to unique investment options that are not available on public markets.

registration rights agreement regulatory

"the Issuer entered into a registration rights agreement with each of the 2026 PIPE Investors (the "Registration Rights Agreement")"

A registration rights agreement is a contract that gives investors the option to have their ownership stakes officially registered with the government, making it easier to sell their shares later. This agreement matters because it provides investors with a clearer path to cash out their investments if they choose, offering more liquidity and confidence in their ability to sell their holdings when desired.

beneficially own financial

"Each of Atlas X, AVA X LP and AVA X LLC may be deemed to beneficially own the shares held by Atlas X"

Beneficially own means having the economic rights and risks of a security—such as the right to receive dividends, sell the shares, or profit from price changes—whether or not your name appears on the official share register. Think of it like renting a car: you use it and reap the benefits even if the title lists someone else. Investors care because beneficial ownership determines who truly controls value, must be disclosed under securities rules, and can signal potential influence or trading activity that affects a stock’s price.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934

(Amendment No. 1)

Q32 Bio Inc.

(Name of Issuer)

Common Stock, par value $0.0001 per share

(Title of Class of Securities)

746964105

(CUSIP Number)

Ommer Chohan
Atlas Venture, 300 Technology Square, 8th Floor
Cambridge, MA, 02139
(857) 201-2700

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

05/26/2026

(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 Number(s): 746964105

1

Name of reporting person

Atlas Venture Fund X, L.P.

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)

WC

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 864,261.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 864,261.00

11

Aggregate amount beneficially owned by each reporting person

864,261.00

12

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

13

Percent of class represented by amount in Row (11)

3.6 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

ATLAS VENTURE ASSOCIATES X, L.P.

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)

AF

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 864,261.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 864,261.00

11

Aggregate amount beneficially owned by each reporting person

864,261.00

12

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

13

Percent of class represented by amount in Row (11)

3.6 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates X, 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)

AF

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 864,261.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 864,261.00

11

Aggregate amount beneficially owned by each reporting person

864,261.00

12

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

13

Percent of class represented by amount in Row (11)

3.6 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Opportunity Fund I, L.P.

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)

WC

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 503,296.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 503,296.00

11

Aggregate amount beneficially owned by each reporting person

503,296.00

12

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

13

Percent of class represented by amount in Row (11)

2.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity I, L.P.

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)

AF

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 503,296.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 503,296.00

11

Aggregate amount beneficially owned by each reporting person

503,296.00

12

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

13

Percent of class represented by amount in Row (11)

2.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity 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)

AF

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 503,296.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 503,296.00

11

Aggregate amount beneficially owned by each reporting person

503,296.00

12

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

13

Percent of class represented by amount in Row (11)

2.1 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Opportunity Fund II, L.P.

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)

WC

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 724,549.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 724,549.00

11

Aggregate amount beneficially owned by each reporting person

724,549.00

12

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

13

Percent of class represented by amount in Row (11)

3.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity II, L.P.

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)

AF

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 724,549.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 724,549.00

11

Aggregate amount beneficially owned by each reporting person

724,549.00

12

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

13

Percent of class represented by amount in Row (11)

3.1 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity 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)

AF

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 724,549.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 724,549.00

11

Aggregate amount beneficially owned by each reporting person

724,549.00

12

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

13

Percent of class represented by amount in Row (11)

3.1 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Opportunity Fund Ill, L.P.

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)

WC

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 625,000.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 625,000.00

11

Aggregate amount beneficially owned by each reporting person

625,000.00

12

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

13

Percent of class represented by amount in Row (11)

2.6 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity III, L.P.

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)

AF

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 625,000.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 625,000.00

11

Aggregate amount beneficially owned by each reporting person

625,000.00

12

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

13

Percent of class represented by amount in Row (11)

2.6 %

14

Type of Reporting Person (See Instructions)

PN

SCHEDULE 13D

CUSIP Number(s): 746964105

1

Name of reporting person

Atlas Venture Associates Opportunity 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)

AF

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 625,000.00
9	Sole Dispositive Power 0.00
10	Shared Dispositive Power 625,000.00

11

Aggregate amount beneficially owned by each reporting person

625,000.00

12

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

13

Percent of class represented by amount in Row (11)

2.6 %

14

Type of Reporting Person (See Instructions)

OO

SCHEDULE 13D

Item 1.	Security and Issuer
(a)	Title of Class of Securities: Common Stock, par value $0.0001 per share
(b)	Name of Issuer: Q32 Bio Inc.
(c)	Address of Issuer's Principal Executive Offices: 830 Winter Street, Waltham, MASSACHUSETTS , 02451.
Item 1 Comment: This Amendment No. 1 to Schedule 13D ("Amendment No. 1") is being filed as an amendment to the statement on Schedule 13D relating to common stock, par value $0.0001 per share of Q32 Bio Inc., a Delaware corporation, as filed with the Securities and Exchange Commission (the "SEC") on April 1, 2024 (the "Original Schedule 13D"). All capitalized terms not otherwise defined herein shall have the meanings ascribed to the terms in the Original Schedule 13D. The Original Schedule 13D is hereby amended and supplemented as follows and, except as expressly amended below, the Original Schedule 13D remains in full force and effect.
Item 2.	Identity and Background
(a)	This Amendment 1 is filed by (i) Atlas Venture Fund X, L.P., a Delaware limited partnership ("Atlas X"), (ii) Atlas Venture Associates X, L.P., a Delaware limited partnership ("AVA X LP"), (iii) Atlas Venture Associates X, LLC, a Delaware limited liability company ("AVA X LLC" and together with Atlas X and AVA X LP, the "Fund X Reporting Persons"), (iv) Atlas Venture Opportunity Fund I, L.P., a Delaware limited partnership ("AVOF"), (v) Atlas Venture Associates Opportunity I, L.P., a Delaware limited partnership ("AVAO LP"), (vi) Atlas Venture Associates Opportunity I, LLC, a Delaware limited liability company ("AVAO LLC" and together with AVOF and AVAO LP, the "Opportunity Fund Reporting Persons"), (vii) Atlas Venture Opportunity Fund II, L.P., a Delaware limited partnership ("AVOF II"), (viii) Atlas Venture Associates Opportunity II, L.P., a Delaware limited partnership ("AVAO II LP"), (ix) Atlas Venture Associates Opportunity II, LLC, a Delaware limited liability company ("AVAO II LLC" and together with AVOF II and AVAO II LP, the "Opportunity Fund II Reporting Persons"), (x) Atlas Venture Opportunity Fund III, L.P., a Delaware limited partnership ("AVOF III"), (xi) Atlas Venture Associates Opportunity III, L.P., a Delaware limited partnership ("AVAO III LP") and (xii) Atlas Venture Associates Opportunity III, LLC, a Delaware limited liability company ("AVAO III LLC" and together with AVOF III and AVAO III LP, the "Opportunity Fund III Reporting Persons" and together with the Fund X Reporting Persons, the Opportunity Fund Reporting Persons and the Opportunity Fund II Reporting Persons, the "Reporting Persons").
(b)	The address of the principal place of business of each of the Reporting Persons is c/o 300 Technology Square, 8th Floor, Cambridge, Massachusetts 02139.
(c)	The principal business of each of the Reporting Persons is the venture capital investment business.
(d)	During the last five years, none of the Reporting Persons has been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors).
(e)	During the last five years, none of the Reporting Persons has been a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.
(f)	Each of Atlas X, AVA X LP, AVOF, AVAO LP, AVOF II, AVAO II LP, AVOF III and AVAO III LP is a Delaware limited partnership. Each of AVA X LLC, AVAO LLC, AVAO II LLC and AVAO III LLC is a Delaware limited liability company.
Item 3.	Source and Amount of Funds or Other Consideration
	Item 3 of the Original Schedule 13D is hereby amended and supplemented as follows: On May 26, 2026, the Issuer entered into a securities purchase agreement with a number of institutional investors (the "2026 PIPE Investors"), including AVOF III, pursuant to which the Issuer agreed to issue and sell shares of common stock and pre-funded warrants in a private placement (the "2026 PIPE"). AVOF III purchased 625,000 shares of common stock of the Issuer at a purchase price of $8.00 per share in the 2026 PIPE. The 2026 PIPE closed on May 28, 2026. The aggregate purchase price for the shares acquired by AVOF III in the 2026 PIPE was $5 million, which was funded from capital contributions by AVOF III's general and limited partners.
Item 5.	Interest in Securities of the Issuer
(a)	As of the date hereof, Atlas X is the record owner of 864,261 shares of Common Stock. AVA X LP is the general partner of Atlas X and AVA X LLC is the general partner of AVA X LP. Each of Atlas X, AVA X LP and AVA X LLC may be deemed to beneficially own the shares held by Atlas X. As of the date hereof, AVOF is the record owner of 503,296 shares of Common Stock. AVAO LP is the general partner of AVOF and AVAO LLC is the general partner of AVAO LP. Each of AVOF, AVAO LP and AVAO LLC may be deemed to beneficially own the shares held by AVOF. As of the date hereof, AVOF II is the record owner of 724,549 shares of Common Stock. AVAO II LP is the general partner of AVOF II and AVAO II LLC is the general partner of AVAO II LP. Each of AVOF II, AVAO II LP and AVAO II LLC may be deemed to beneficially own the shares held by AVOF II. As of the date hereof, AVOF III is the record owner of 625,000 shares of Common Stock. AVAO III LP is the general partner of AVOF III and AVAO III LLC is the general partner of AVAO III LP. Each of AVOF III, AVAO III LP and AVAO III LLC may be deemed to beneficially own the shares held by AVOF III. Each of the Fund X Reporting Persons, the Opportunity Fund Reporting Persons, the Opportunity Fund II Reporting Persons and the Opportunity Fund III Reporting Persons may be deemed to beneficially own 3.6%, 2.1%, 3.1% and 2.6%, respectively, of the Issuer's outstanding Common Stock, which percentages are calculated based upon 23,681,415 shares of Common Stock outstanding as of May 28, 2026, which is the sum of 16,956,415 shares of Common Stock outstanding as of May 26, 2026 and 6,725,000 shares of Common Stock sold in the 2026 PIPE, as reported in the Issuer's Current Report on Form 8-K filed with the SEC on May 27, 2026. Collectively, the Reporting Persons beneficially own an aggregate of 2,717,106 shares of Common Stock, which represents an estimated 11.5% of the Issuer's outstanding Common Stock. The Fund X Reporting Persons, the Opportunity Fund Reporting Persons, the Opportunity Fund II Reporting Persons and the Opportunity Fund III Reporting Persons are under common control and as a result, the Reporting Persons may be deemed to be members of a group. However, the Reporting Persons disclaim such group membership, and this Schedule 13D shall not be deemed an admission that the Reporting Persons are members of a group for purposes of Section 13 or for any other purposes.
(b)	Each of Atlas X, AVA X LP and AVA X LLC has shared voting and dispositive power over 864,261 shares held by Atlas X. Each of AVOF, AVAO LP and AVAO LLC has shared voting and dispositive power over 503,296 shares held by AVOF. Each of AVOF II, AVAO II LP and AVAO II LLC has shared voting and dispositive power over 724,549 shares held by AVOF II. Each of AVOF III, AVAO III LP and AVAO III LLC has shared voting and dispositive power over 625,000 shares held by AVOF III.
(c)	Except as set forth herein, none of the Reporting Persons has effected any transactions in shares of the Issuer's Common Stock during the last 60 days.
(d)	No other person is known by the Reporting Persons to have the right to receive or the power to direct the receipt of dividends from, or the proceeds from the sale of, the shares of Common Stock beneficially owned by the Reporting Persons.
(e)	Not applicable.
Item 6.	Contracts, Arrangements, Understandings or Relationships With Respect to Securities of the Issuer
	Item 6 of the Original Schedule 13D is hereby amended and supplemented as follows: Registration Rights Agreement In connection with the 2026 PIPE, the Issuer entered into a registration rights agreement with each of the 2026 PIPE Investors (the "Registration Rights Agreement"), pursuant to which the Issuer is required to prepare and file a registration statement (the "Registration Statement") with the Securities and Exchange Commission (the "SEC") under the Securities Act, covering the resale of the shares and shares issuable upon exercise of pre-funded warrants issued in the 2026 PIPE. The Issuer is required to file the Registration Statement with the SEC within 50 days of the closing date of the 2026 PIPE and is required to have the Registration Statement declared effective by the SEC in accordance with the terms of the Registration Rights Agreement. The foregoing description of the Registration Rights Agreement is not complete and is qualified in its entirety by reference to the full text of the form of Registration Rights Agreement, which is filed as an exhibit to this Amendment No. 1 and incorporated herein by reference.
Item 7.	Material to be Filed as Exhibits.
	99.1 Joint Filing Agreement 99.2 Form of Registration Rights Agreement (incorporated by reference to Exhibit 10.2 to the Issuer's Current Report on Form 8-K, filed with the SEC on May 27, 2026).

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.

Atlas Venture Fund X, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates X, L.P., its general partner, By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, CFO
Date:	05/28/2026

ATLAS VENTURE ASSOCIATES X, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates X, LLC, its general partner, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates X, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Opportunity Fund I, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity I, L.P., its GP, By: Atlas Venture Associates Opportunity I, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity I, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity I, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity I, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Opportunity Fund II, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity II, L.P., its GP, By: Atlas Venture Associates Opportunity II, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity II, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity II, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity II, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Opportunity Fund Ill, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity III, L.P., its GP, By: Atlas Venture Associates Opportunity III, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity III, L.P.

Signature:	/s/ Ommer Chohan
Name/Title:	By: Atlas Venture Associates Opportunity III, LLC, its GP, By: Ommer Chohan, CFO
Date:	05/28/2026

Atlas Venture Associates Opportunity III, LLC

Signature:	/s/ Ommer Chohan
Name/Title:	By: Ommer Chohan, CFO
Date:	05/28/2026

FAQ

What stake in Q32 Bio (QTTB) do the Atlas Venture funds report?

The Atlas Venture reporting entities disclose holding an aggregate 2,717,106 Q32 Bio common shares, representing about 11.5% of the company’s 23,681,415 shares outstanding as of May 28, 2026.

How many Q32 Bio shares did Atlas Venture buy in the 2026 PIPE?

Atlas Venture Opportunity Fund III purchased 625,000 Q32 Bio common shares in the 2026 PIPE. The shares were acquired at a purchase price of $8.00 per share under a securities purchase agreement.

What was the total amount Atlas Venture invested in Q32 Bio’s 2026 PIPE?

Atlas Venture Opportunity Fund III invested $5 million in the 2026 PIPE. This reflects 625,000 common shares bought at $8.00 per share, funded by capital contributions from its general and limited partners.

How did the 2026 PIPE affect Q32 Bio’s shares outstanding?

After the 2026 PIPE, Q32 Bio had 23,681,415 common shares outstanding. This total combines 16,956,415 shares previously outstanding and 6,725,000 new shares sold in the private placement, as reported in a Form 8-K.

What ownership percentages do individual Atlas Venture funds hold in Q32 Bio?

Atlas Venture Fund X entities report 3.6%, Opportunity Fund I entities 2.1%, Opportunity Fund II entities 3.1%, and Opportunity Fund III entities 2.6% of Q32 Bio’s common stock, based on 23,681,415 shares outstanding.

What registration rights did Q32 Bio grant to the 2026 PIPE investors?

Q32 Bio entered a registration rights agreement requiring it to file a registration statement covering resale of PIPE shares and pre-funded warrant shares. The company must file within 50 days of closing and obtain effectiveness under agreed terms.