Gritstone bio (GRTSQ) SC 13G Gritstone bio / Frazier Life Sciences Public Fund ownership change

SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, DC 20549

SCHEDULE 13G

UNDERTHE SECURITIES EXCHANGE ACTOF 1934

(Amendment No.     )*

Gritstone bio, Inc.

(Name of Issuer)

Common Stock

(Title of Class of Securities)

39868T 105

(CUSIP Number)

September 17, 2021

(Date of Event Which Requires Filing of this Statement)

Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

☐ Rule 13d-1(b)

☒ Rule 13d-1(c)

☐ Rule 13d-1(d)

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter the disclosures provided in a prior cover page.

The information required in 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).

CUSIP No. 39868T 105

1.	Names of Reporting Persons Frazier Life Sciences Public Fund L.P.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 3,636,364 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 3,636,364 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 3,636,364 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 6.7% (2)
12.	Type of Reporting Person (see instructions) PN

(1) Consists of 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons FHMLSP, L.P.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 3,636,364 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 3,636,364 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 3,636,364 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 6.7% (2)
12.	Type of Reporting Person (see instructions) PN

(1) Consists of 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons FHMLSP, L.L.C.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 3,636,364 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 3,636,364 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 3,636,364 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 6.7% (2)
12.	Type of Reporting Person (see instructions) OO

(1) Consists of 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Frazier Healthcare VII, L.P.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 802,259 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 802,259 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 802,259 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.5% (2)
12.	Type of Reporting Person (see instructions) PN

(1) Consists of 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. FHM VII, L.P. is the general partner of Frazier Healthcare VII, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Frazier Healthcare VII-A, L.P.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 228,621 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 228,621 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 228,621 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 0.4% (2)
12.	Type of Reporting Person (see instructions) PN

(1) Consists of 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P. FHM VII, L.P. is the general partner of Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII-A, L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons FHM VII, L.P.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 1,030,880 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 1,030,880 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,030,880 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (2)
12.	Type of Reporting Person (see instructions) PN

(1) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P (collectively, the “FH Shares”). FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the FH Shares.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons FHM VII, L.L.C.
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization Delaware

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 1,030,880 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 1,030,880 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,030,880 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (2)
12.	Type of Reporting Person (see instructions) OO

(1) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P (collectively, the “FH Shares”). FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the FH Shares.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons James N. Topper
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 61,307 shares (1)
	6.	Shared Voting Power 4,667,244 shares (2)
	7.	Sole Dispositive Power 61,307 shares (1)
	8.	Shared Dispositive Power 4,667,244 shares (2)

9.	��	Aggregate Amount Beneficially Owned by Each Reporting Person 4,728,551 shares (1)(2)
10.		Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.		Percent of Class Represented by Amount in Row 9 8.7% (3)
12.		Type of Reporting Person (see instructions) IN

(1) Consists of 61,307 shares of Common Stock held directly by James Topper.

(2) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P., (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P., and (iii) 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(3) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Patrick J. Heron
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 61,307 shares (1)
	6.	Shared Voting Power 4,667,244 shares (2)
	7.	Sole Dispositive Power 61,307 shares (1)
	8.	Shared Dispositive Power 4,667,244 shares (2)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 4,728,551 shares (1)(2)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 8.7% (3)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of (i) 61,307 shares of Common Stock held directly by The Heron Living Trust dated 11/30/2004, which Patrick Heron is the trustee and has voting and investment power over such shares.

(2) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P., (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P., and (iii) 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(3) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Albert Cha
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 3,636,364 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 3,636,364 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 3,636,364 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 6.7% (2)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons James Brush
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 3,636,364 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 3,636,364 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 3,636,364 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 6.7% (2)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of 3,636,364 shares of Common Stock held directly by Frazier Life Sciences Public Fund L.P. FHMLSP, L.P. is the general partner of Frazier Life Sciences Public Fund L.P. and FHMLSP, L.L.C. is the general partner of FHMLSP, L.P. Patrick J. Heron, James N. Topper, Albert Cha and James Brush are the members of FHMLSP, L.L.C. and therefore share voting and investment power over the shares held by Frazier Life Sciences Public Fund L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Alan Frazier
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 9,376 shares (1)
	6.	Shared Voting Power 1,030,880 shares (2)
	7.	Sole Dispositive Power 9,376 shares (1)
	8.	Shared Dispositive Power 1,030,880 shares (2)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,040,256 shares (1)(2)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (3)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of 9,376 shares of Common Stock held directly by Frazier & Company, Inc., of which Alan Frazier is the President and has voting and investment power over such shares.

(2) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P.

(3) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Nader Naini
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 0 shares
	6.	Shared Voting Power 1,030,880 shares (1)
	7.	Sole Dispositive Power 0 shares
	8.	Shared Dispositive Power 1,030,880 shares (1)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,030,880 shares (1)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (2)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P.

(2) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Brian Morfitt
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 5,722 shares (1)
	6.	Shared Voting Power 1,030,880 shares (2)
	7.	Sole Dispositive Power 5,722 shares (1)
	8.	Shared Dispositive Power 1,030,880 shares (2)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,036,602 shares (1)(2)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (3)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of 5,722 shares of Common Stock held directly by Brian Morfitt.

(2) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P.

(3) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

CUSIP No. 39868T 105

1.	Names of Reporting Persons Nathan Every
2.	Check the Appropriate Box if a Member of a Group (see instructions) (a)  ☐ (b)  ☒
3.	SEC USE ONLY
4.	Citizenship or Place of Organization United States Citizen

Number of     Shares     Beneficially     Owned by     Each     Reporting     Person With:	5.	Sole Voting Power 8,221 shares (1)
	6.	Shared Voting Power 1,030,880 shares (2)
	7.	Sole Dispositive Power 8,221 shares (1)
	8.	Shared Dispositive Power 1,030,880 shares (2)

9.	Aggregate Amount Beneficially Owned by Each Reporting Person 1,039,101 shares (1)(2)
10.	Check if the Aggregate Amount in Row (9) Excludes Certain Shares (see instructions)  ☐
11.	Percent of Class Represented by Amount in Row 9 1.9% (3)
12.	Type of Reporting Person (see instructions) IN

(1) Consists of 8,221 shares of Common Stock held directly by Nathan Every.

(2) Consists of (i) 802,259 shares of Common Stock held directly by Frazier Healthcare VII, L.P. and (ii) 228,621 shares of Common Stock held directly by Frazier Healthcare VII-A, L.P. FHM VII, L.P. is the general partner of both Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P. and FHM VII, L.L.C. is the general partner of FHM VII, L.P. Alan Frazier, Nader Naini, Patrick Heron, James Topper, Nathan Every, and Brian Morfitt are the members of FHM VII, L.L.C. and therefore share voting and investment power over the shares held by Frazier Healthcare VII, L.P. and Frazier Healthcare VII-A, L.P.

(3) Based on (i) 49,447,693 shares of Common Stock outstanding on July 30, 2021 as set forth in the Issuer’s Form 10-Q filed with the SEC on August 5, 2021 and (ii) 5,000,000 shares of Common Stock that were sold on September 17, 2021 as described in the Issuer’s Current Form 8-K filed with the SEC on September 17, 2021.

Item 1(a). Name of Issuer: Gritstone bio, Inc.

Item 1(b). Address of Issuer’s Principal Executive Offices: 5959 Horton Street, Suite 300, Emeryville, California 94608

Item 2(a). Name of Person Filing:

The entities and persons filing this statement (collectively, the “Reporting Persons”) are:

Frazier Healthcare VII, L.P. (“FH-VII”)

Frazier Healthcare VII-A, L.P. (“FH-VIIA”)

FHM VII, L.P. (“FHM-VII L.P.”)

FHM VII, L.L.C. (“FHM-VII LLC”)

Frazier Life Sciences Public Fund L.P. (“FLSPF”)

FHMLSP, L.P.

FHMLSP, L.L.C.

James Topper (“Topper”)

Patrick Heron (“Heron”)

Alan Frazier (“Frazier”)

Nader Naini (“Naini”)

Nathan Every (“Every”)

Brian Morfitt (“Morfitt”)

Albert Cha (“Cha”)

James Brush (“Brush” and together with Topper, Heron, Frazier, Naini, Every and Brush, the “Members”)

Item 2(b). Address of Principal Business Office or, if none, Residence:

The address and principal business office of the Reporting Persons is:

c/o Frazier Healthcare Partners

601 Union Street, Suite 3200

Seattle, Washington 98101

Item 2(c). Citizenship:

Entities:	FH-VII	-	Delaware, U.S.A.
	FH-VIIA	-	Delaware, U.S.A.
	FHM-VII L.P.	-	Delaware, U.S.A.
	FHM-VII LLC	-	Delaware, U.S.A.
	FLSPF	-	Delaware, U.S.A.
	FHMLSP, L.P.	-	Delaware, U.S.A.
	FHMLSP, L.L.C.	-	Delaware, U.S.A.
Individuals:	Topper	-	United States Citizen
	Heron	-	United States Citizen
	Frazier	-	United States Citizen
	Naini	-	United States Citizen
	Every	-	United States Citizen
	Morfitt	-	United States Citizen
	Cha	-	United States Citizen
	Brush	-	United States Citizen

Item 2(d). Title of Class of Securities: Common Stock

Item 2(e). CUSIP Number: 39868T 105

Item 3. If this statement is filed pursuant to §§240.13d-1(b), or 240.13d-2(b) or (c), check whether the person filing is a:

(a) ☐ Broker or dealer registered under Section 15 of the Act (15 U.S.C. 78o);

(b) ☐ Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c);

(c) ☐ Insurance company as defined in section 3(a)19) of the Act (15 U.S.C. 78c);

(d) ☐ Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C. 80a-8);

(e) ☐ An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

(f) ☐ An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

(g) ☐ A parent holding company or control person in accordance with §240.13d-1(b)(1)(ii)(G);

(h) ☐ A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i) ☐ A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of      1940 (15 U.S.C. 80a-3);

(j) ☐ A non-U.S. institution in accordance with §240.13d–1(b)(1)(ii)(J);

(k) ☐ Group, in accordance with §240.13d–1(b)(1)(ii)(K).

     If filing as a non-U.S. institution in accordance with §240.13d–1(b)(1)(ii)(J), please specify the type of institution:         

Item 4. Ownership

Provide the following information regarding the aggregate number and percentage of the class of securities of the Issuer identified in Item 1.

(a) Amount Beneficially Owned: See Row 9 of cover page for each Reporting Person.

(b) Percent of Class: See Row 11 of cover page for each Reporting Person

(c) Number of shares as to which the person has:

(i) Sole power to vote or to direct the vote: See Row 5 of cover page for each Reporting Person.

(ii) Shared power to vote or to direct the vote: See Row 6 of cover page for each Reporting Person.

(iii) Sole power to dispose or to direct the disposition of: See Row 7 of cover page for each Reporting Person.

(iv) Shared power to dispose or to direct the disposition of: See Row 8 of cover page for each Reporting Person.

Item 5. Ownership of 5 Percent or Less of a Class

If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than 5 percent of the class of securities, check the following  ☐.

Item 6. Ownership of More than 5 Percent on Behalf of Another Person

Not applicable.

Item 7. Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person.

Not applicable.

Item 8. Identification and Classification of Members of the Group

Each member of the group is identified on Exhibit A to this Schedule 13G.

Item 9. Notice of Dissolution of a Group

Not applicable.

Item 10. Certification

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect, other than activities solely in connection with a nomination under § 240.14a-11.

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.

Date:	September 21, 2021	FRAZIER HEALTHCARE VII, L.P.
		By FHM VII, L.P., its general partner
		By FHM VII, L.L.C., its general partner
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FRAZIER HEALTHCARE VII-A, L.P.
		By FHM VII, L.P., its general partner
		By FHM VII, L.L.C., its general partner
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FHM VII, L.P.
		By FHM VII, L.L.C., its general partner
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FHM VII, L.L.C.
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FRAZIER LIFE SCIENCES PUBLIC FUND L.P.
		By: FHMLSP, L.P., its General Partner
		By: FHMLSP, L.L.C., its General Partner
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FHMLSP, L.P.
		By: FHMLSP, L.L.C., its General Partner
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer
Date:	September 21, 2021	FHMLSP, L.L.C.
		By:	/s/ Steve R. Bailey
			Steve R. Bailey, Chief Financial Officer

Date: September 21, 2021 By: *

			James Topper
Date:	September 21, 2021	By:	*

			Patrick Heron
Date:	September 21, 2021	By:	*

			Nader Naini
Date:	September 21, 2021	By:	*

			Nathan Every
Date:	September 21, 2021	By:	*

			Brian Morfitt
Date:	September 21, 2021	By:	*

			Alan Frazier
Date:	September 21, 2021	By:	**

			Albert Cha
Date:	September 21, 2021	By:	**

			James Brush
Date:	September 21, 2021	*By:	/s/ Steve R. Bailey
			Steve R. Bailey, as Attorney-in-Fact

* This Schedule 13G was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on March 29, 2016.

** This Schedule 13G was executed by Steve R. Bailey on behalf of the individuals listed above pursuant to a Power of Attorney, a copy of which was filed with the SEC on August 16, 2021.

Exhibit Index

Exhibit A -        Agreement regarding filing of joint Schedule 13G.