Mark C. McKenna - Jan 17, 2023 Form 4 Insider Report for Prometheus Biosciences, Inc. (RXDX)

Role: Chairman, President & CEO, Director
Signature: /s/ Timothy K. Andrews, attorney-in-fact for Mark C. McKenna
Stock symbol: RXDX
Transactions as of: Jan 17, 2023
Transactions value $: -$2,902,250
Form type: 4
Date filed: 1/19/2023, 07:39 PM
Previous filing: Dec 13, 2022
Next filing: Feb 17, 2023

Transactions Table

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Ownership	Footnotes
transaction	RXDX	Common Stock	Options Exercise	$72.5K	+25K	+45.34%	$2.90^*	80.1K	Jan 17, 2023	Direct	F1
transaction	RXDX	Common Stock	Sale	-$2.97M	-25K	-31.19%	$118.99	55.1K	Jan 17, 2023	Direct	F1, F2

Derivative Securities (e.g., puts, calls, warrants, options, convertible securities)

Type	Sym	Class	Transaction	Value $	Shares	Change %	* Price $	Shares After	Date	Underlying Class	Amount	Exercise Price	Ownership	Footnotes
transaction	RXDX	Stock Option (Right to Buy)	Options Exercise	$0	-25K	-6.97%	$0.00	334K	Jan 17, 2023	Common Stock	25K	$2.90	Direct	F1, F3

* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id	Content
F1	The transactions reported in this Form 4 were effected pursuant to a Rule 10b5-1 Trading Plan adopted by the Reporting Person in April 2022.
F2	The price reported in Column 4 is a weighted average price. The Reporting Person undertakes to provide to the Issuer, any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price.
F3	25% of the shares subject to the option vested and became exercisable on September 9, 2020, and 1/48th of the shares subject to the option shall vest monthly thereafter, subject to the Reporting Person's continued service with the Issuer through each vest date.