William Blair LLC discloses 8.6% stake in Twist Bioscience (NASDAQ: TWST)

Rhea-AI Filing Summary

Twist Bioscience Corp ownership update: William Blair Investment Management, LLC filed Amendment No. 2 to a Schedule 13G/A reporting beneficial ownership of 5,269,718 shares of Common Stock, representing 8.6% of the class. The filer reports sole voting power over 4,836,983 shares and sole dispositive power over 5,269,718 shares. The filing is signed by the Chief Compliance Officer on 05/07/2026.

Key Figures

Beneficial ownership: 5,269,718 shares Percent of class: 8.6% Sole voting power: 4,836,983 shares +2 more

5 metrics

Beneficial ownership 5,269,718 shares reported in Schedule 13G/A Amendment No. 2

Percent of class 8.6% percent of common stock beneficially owned

Sole voting power 4,836,983 shares shares over which the filer has sole vote

Sole dispositive power 5,269,718 shares shares over which the filer has sole disposition

Filing signature date 05/07/2026 date the amendment was signed

Key Terms

Schedule 13G/A, beneficial ownership, sole dispositive power, sole voting power

4 terms

Schedule 13G/A regulatory

"Amendment No. 2 to a Schedule 13G/A reporting beneficial ownership"

A Schedule 13G/A is an amended public filing with the U.S. securities regulator that updates a previous Schedule 13G, disclosing when an individual or group holds a substantial (typically over 5%) stake in a company and is claiming a passive, non‑controlling intent. Investors monitor these updates because rising or falling holdings can signal changing confidence, potential future moves, or shifts in voting power — like watching a public ledger where large shareholders quietly adjust their positions.

beneficial ownership financial

"Amount beneficially owned: 5,269,718 and Percent of class: 8.6%"

Beneficial ownership means the person or entity that actually enjoys the benefits of owning shares or other assets — such as receiving dividends, voting rights, or price gains — even if the legal title is held in another name. For investors it matters because knowing who truly controls and profits from a company reveals who can influence decisions, exposes potential conflicts of interest or hidden concentration of power, and affects transparency and risk in the stock.

sole dispositive power regulatory

"Sole power to dispose or to direct the disposition of: 5,269,718"

Sole dispositive power is the exclusive legal authority to decide what happens to a security — for example, whether to sell, transfer, or retain shares — without needing anyone else’s permission. Investors care because it signals who truly controls the economic outcome of an investment: like holding the only key to a safe, the holder can realize gains or losses and may trigger regulatory reporting, insider rules, or influence over corporate ownership.

sole voting power regulatory

"Sole power to vote or to direct the vote: 4,836,983"

Sole voting power is the exclusive right to cast votes attached to a shareholder’s stock without needing approval from anyone else. Like holding the only remote control for a TV, it lets that holder decide corporate matters such as board members, mergers, and policy changes, making it important to investors because it concentrates control and can strongly influence a company’s strategy and the value of its shares.

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

SCHEDULE 13G

UNDER THE SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 2)

Twist Bioscience Corp

(Name of Issuer)

Common Stock

(Title of Class of Securities)

90184D100

(CUSIP Number)

03/31/2026

(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)

schemaVersion:

SCHEDULE 13G

CUSIP Number(s): 90184D100

1

Names of Reporting Persons

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

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 4,836,983.00
6	Shared Voting Power 0.00
7	Sole Dispositive Power 5,269,718.00
8	Shared Dispositive Power 0.00

9

Aggregate Amount Beneficially Owned by Each Reporting Person

5,269,718.00

10

Check box if the aggregate amount in row (9) excludes certain shares (See Instructions)

11

Percent of class represented by amount in row (9)

8.6 %

12

Type of Reporting Person (See Instructions)

IA

SCHEDULE 13G

Item 1.
(a)	Name of issuer: Twist Bioscience Corp
(b)	Address of issuer's principal executive offices: 681 GATEWAY BLVD., 681 GATEWAY BLVD., SOUTH SAN FRANCISCO, CALIFORNIA, 94080.
Item 2.
(a)	Name of person filing: William Blair Investment Management, LLC
(b)	Address or principal business office or, if none, residence: 150 North Riverside Plaza, Chicago, IL 60606
(c)	Citizenship: Delaware
(d)	Title of class of securities: Common Stock
(e)	CUSIP No.: 90184D100
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). If filing as a non-U.S. institution in accordance with § 240.13d-1(b)(1)(ii)(J), please specify the type of institution:
(k)	Group, in accordance with Rule 240.13d-1(b)(1)(ii)(K).
Item 4.	Ownership
(a)	Amount beneficially owned: 5,269,718
(b)	Percent of class: 8.6%
(c)	Number of shares as to which the person has:
	(i) Sole power to vote or to direct the vote: 4,836,983
	(ii) Shared power to vote or to direct the vote: 0
	(iii) Sole power to dispose or to direct the disposition of: 5,269,718
	(iv) Shared power to dispose or to direct the disposition of: 0
Item 5.	Ownership of 5 Percent or Less of a Class.
	Not Applicable
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.
	Not Applicable
Item 9.	Notice of Dissolution of Group.
	Not Applicable

Item 10.

Certifications:

By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and 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.

WILLIAM BLAIR INVESTMENT MANAGEMENT, LLC

Signature:	Telmo Martins
Name/Title:	Chief Compliance Officer
Date:	05/07/2026

FAQ

What stake did William Blair report in Twist Bioscience (TWST)?

William Blair reported beneficial ownership of 5,269,718 shares, equal to 8.6% of Twist Bioscience's common stock. The filing lists sole voting power over 4,836,983 shares and sole dispositive power over 5,269,718 shares.

What type of filing was submitted for TWST?

An Amendment No. 2 to a Schedule 13G/A was filed, updating beneficial ownership information for Twist Bioscience. The filing amends prior Schedule 13G disclosures and reports current holdings and voting/dispositive powers.

Who signed the Schedule 13G/A amendment for TWST?

The amendment was signed by Telmo Martins, Chief Compliance Officer of William Blair Investment Management, LLC, with the signature dated 05/07/2026. The filer’s listed jurisdiction is Delaware.

How many shares does William Blair have power to vote for TWST?

William Blair reports sole voting power over 4,836,983 shares of common stock. The filing shows 0 shares of shared voting power and 0 shared dispositive power.

Where is Twist Bioscience's principal executive office listed in the filing?

The filing lists the issuer's principal executive office at 681 Gateway Blvd., South San Francisco, California 94080. This address is provided under the item identifying the issuer.