Twist Bioscience CEO sells 45,736 shares for taxes

The sales had different stated mechanics: one followed a June 2026 trading plan, while the other covered tax withholding from Restricted Stock Unit vesting.

Rhea-AI Filing Summary

Twist Bioscience Corp (TWST) reported two direct common-stock sales by Chief Executive Officer Emily M. Leproust: 655 shares on October 1, 2026, at $200.0000 per share under a Rule 10b5-1 plan adopted June 15, 2026; and 45,736 shares on October 2, 2026, at $188.8840 per share to cover tax withholding from Restricted Stock Unit vesting. The latter sale was mandated under the issuer’s equity incentive plans and was not discretionary. She also reported options covering 131,290 common shares at a $23.3300 exercise price, expiring October 23, 2029, and 64,950 common shares at a $67.8500 exercise price, expiring August 31, 2030.

Insider Trade Summary 10b5-1

Net Seller: 46,391 shares

Net Sell 4 txns

Insider Leproust Emily M.

Role Chief Executive Officer

Sold 46,391 shs ($8.77M)

Type	Security	Shares	Price	Value
Sale	Common Stock F2	45,736	$188.884	$8.64M
Sale	Common Stock F1	655	$200.00	$131K
holding	Employee Stock Option (right to buy) F3	--	--	--
holding	Employee Stock Option (right to buy) F4	--	--	--

Holdings After Transaction: Common Stock — 567,308 shares (Direct); Employee Stock Option (right to buy) — 196,240 contracts (Direct)

Footnotes (4)

1. F1. The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person on June 15, 2026.
2. F2. Represents the number of shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.
3. F3. 25% of the shares subject to the option vested on October 24, 2020, and 1/48th of the shares subject to the option vest on each monthly anniversary thereafter, subject to the Reporting Person's continuous service through each vesting date.
4. F4. Represents performance stock options granted to the reporting person on September 1, 2020, that vested and became exercisable on December 19, 2022 as a result of the reporting person having met the applicable performance criteria.

Key Figures

Shares sold: 655 shares Sale price: $200.0000 per share Shares sold: 45,736 shares +3 more

6 metrics

Shares sold 655 shares October 1, 2026

Sale price $200.0000 per share October 1, 2026

Shares sold 45,736 shares October 2, 2026; tax withholding from Restricted Stock Unit vesting

Sale price $188.8840 per share October 2, 2026

Employee stock options 131,290 underlying common shares; $23.3300 exercise price Expiration: October 23, 2029

Employee stock options 64,950 underlying common shares; $67.8500 exercise price Expiration: August 31, 2030

Key Terms

Rule 10b5-1 trading plan, sell to cover, Restricted Stock Units, performance stock options

4 terms

Rule 10b5-1 trading plan regulatory

"pursuant to a Rule 10b5-1 trading plan"

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.

sell to cover financial

"funded by a "sell to cover" transaction"

Sell to cover is when a person who receives company stock through options or awards sells just enough shares immediately to pay required taxes, exercise costs, or fees, keeping the rest. Think of it like cashing part of a bonus to cover the tax bill so you can keep the remainder. For investors, it can create predictable small selling pressure and slightly change the number of shares actually held by insiders without increasing long‑term dilution.

Restricted Stock Units financial

"vesting of Restricted Stock Units"

Restricted stock units are a type of company reward where employees are promised shares of stock, but they only fully own these shares after meeting certain conditions, like staying with the company for a set time. They matter because they can become valuable assets and are often used to motivate employees to help the company succeed.

performance stock options financial

"Represents performance stock options granted"

FAQ

AI-generated questions and answers. How Rhea-AI works. Not financial advice.

How many TWST shares did CEO Emily M. Leproust sell, and at what prices?

Emily M. Leproust reported selling 655 shares on October 1, 2026, at $200.0000 per share, and 45,736 shares on October 2, 2026, at $188.8840 per share.

What vesting terms are reported for Emily M. Leproust’s TWST options?

One option award had 25% of its shares vest on October 24, 2020, followed by 1/48th on each monthly anniversary, subject to continuous service through each vesting date. The performance stock options granted September 1, 2020, vested and became exercisable on December 19, 2022, after the applicable performance criteria were met.

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

Form 4 Insider Transactions: What Each Field Means →

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

Available on EDGAR 10/05/2026 - 04:05 PM Accepted by SEC EDGAR 10/05/2026 - 04:05 PM Learn about SEC filing dates

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^*

Leproust Emily M.

(Last) (First) (Middle)

C/O TWIST BIOSCIENCE CORPORATION

681 GATEWAY BLVD.

(Street)

SOUTH SAN FRANCISCO CALIFORNIA 94080

(City) (State) (Zip)

UNITED STATES

(Country)

2. Issuer Name and Ticker or Trading Symbol
Twist Bioscience Corp [ TWST ]

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

X	Director		10% Owner
X	Officer (give title below)		Other (specify below)
	Chief Executive Officer

2a. Foreign Trading Symbol

3. Date of Earliest Transaction (Month/Day/Year)
10/01/2026

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
Common Stock	10/01/2026		S(1)		655	D	$200	613,044	D
Common Stock	10/02/2026		S		45,736(2)	D	$188.884	567,308	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
Employee Stock Option (right to buy)	$23.33							(3)	10/23/2029	Common Stock	131,290		131,290	D
Employee Stock Option (right to buy)	$67.85							12/19/2022	08/31/2030	Common Stock	64,950		64,950(4)	D

Explanation of Responses:

1. The transactions reported on this Form 4 were effected pursuant to a Rule 10b5-1 trading plan previously adopted by the Reporting Person on June 15, 2026.

2. Represents the number of shares required to be sold by the Reporting Person to cover tax withholding obligations in connection with the vesting of Restricted Stock Units. These sales are mandated by the Issuer's election under its equity incentive plans to require the satisfaction of a tax withholding obligation to be funded by a "sell to cover" transaction and do not represent discretionary trades by the Reporting Person.

3. 25% of the shares subject to the option vested on October 24, 2020, and 1/48th of the shares subject to the option vest on each monthly anniversary thereafter, subject to the Reporting Person's continuous service through each vesting date.

4. Represents performance stock options granted to the reporting person on September 1, 2020, that vested and became exercisable on December 19, 2022 as a result of the reporting person having met the applicable performance criteria.

Remarks:

	/s/ Kendra Fox, as Attorney-in-Fact for Emily M. Leproust	10/05/2026
	** 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)