Robert Chess - 17 Mar 2026 Form 4 Insider Report for Twist Bioscience Corp (TWST)

Reporting relationship: Director
Issuer ticker: TWST
Reported as of: 17 Mar 2026
Net transaction value: -$470,000
SEC form: 4
Accepted by SEC: 19 Mar 2026, 16:05:15 UTC
Prior SEC filing: 18 Feb 2026
Source filing: View source filing
Reporting owner signature: /s/ Kendra Fox, as Attorney-in-Fact for Robert Chess

Key filing fact

Robert Chess filed Form 4 for Twist Bioscience Corp (TWST) on 19 Mar 2026.

Key facts

This page summarizes Robert Chess's Form 4 filing for Twist Bioscience Corp (TWST).
3 reported transactions and 1 derivative row are listed below.
Accepted by SEC: 19 Mar 2026, 16:05.

Change

Previous filing in this sequence was filed on 18 Feb 2026.
Current net transaction value: -$470,000.

Research use

This tells you what this filing adds before you inspect full transaction and derivative tables.
You can trace every row back to the original SEC filing document.

Evidence

Filed on Form 4

Ownership activity is grounded in SEC Form 4 disclosures.

View source filing

Reporting Owners (1)

CIK 0001227886 Primary reporting owner

CHESS ROBERT

Relationship: Director
Address: C/O TWIST BIOSCIENCE CORPORATION, 681 GATEWAY BLVD., SOUTH SAN FRANCISCO
Signature: /s/ Kendra Fox, as Attorney-in-Fact for Robert Chess
Signature date: 19 Mar 2026

Reported non-derivative transactions

Shares, units, or other non-derivative securities reported in this filing.

TWST transaction

Common Stock

Options Exercise

Transaction value
Shares: +10,000
Change %: +47%
Price: $11.89^*
Shares after: 31,084
Date: 17 Mar 2026
Ownership: Direct
Footnotes: F1

TWST transaction

Common Stock

Sale

Transaction value: $470,000
Shares: -10,000
Change %: -32%
Price: $47.00
Shares after: 21,084
Date: 17 Mar 2026
Ownership: Direct
Footnotes: F1

TWST holding

Common Stock

No transaction description listed

Transaction value
Shares
Change %
Price
Shares after: 42,528
Date: 17 Mar 2026
Ownership: By the Chess 1997 Trust
Footnotes: F2

Reported derivative securities

Options, warrants, convertible securities, or similar derivative positions disclosed in the filing.

TWST transaction Derivative

Stock Option (right to buy)

Options Exercise

Transaction value
Shares: -10,000
Change %: -35%
Price: $0.000000^*
Shares after: 18,417
Date: 17 Mar 2026
Ownership: Direct
Underlying class: Common Stock
Underlying amount: 10,000
Exercise price: $11.89
Footnotes: F1, F3

^* marks a reported price that did not pass the local price check.

Additional SEC filing notes

Filing notes and footnotes

Rule 10b5-1 trading plan

These transactions were reported as open-market trades under a Rule 10b5-1 plan. The plan lets an insider set trading instructions in advance, which can reduce the risk of trading while in possession of material nonpublic information.

Original filing language: transaction made pursuant to a contract, instruction, or written plan intended to satisfy Rule 10b5-1(c).

Explanation of responses 3 footnotes

Footnote 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 December 10, 2025.

Footnote F2

The Reporting Person and his spouse are the sole trustees and the sole beneficiaries of the Chess 1997 Trust.

Footnote F3

The option is immediately exercisable. 10% of the shares subject to the option vested on September 13, 2018, 15% of the shares subject to the option vested on March 24, 2019, and 1/48th of the shares subject to the option vested on each monthly anniversary thereafter, subject to the Reporting Person's continuous service through each vesting date.