CASTLE BIOSCIENCES INC — Director's Dealing 2019

Jul 31, 2019

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: CASTLE BIOSCIENCES INC (CSTL)
CIK: 0001447362
Period of Report: 2019-07-29

Reporting Person: Cook Joseph C. III (Director, 10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2019-07-29	Common Stock	C	1336927	—	Acquired	1336927	Indirect
2019-07-29	Common Stock	C	97428	$12.80	Acquired	1434355	Indirect
2019-07-29	Common Stock	P	312500	$16.00	Acquired	1746855	Indirect
2019-07-29	Common Stock	C	169086	—	Acquired	169086	Direct
2019-07-29	Common Stock	C	16722	$12.80	Acquired	185808	Direct
2019-07-29	Common Stock	P	22245	$16.00	Acquired	208053	Direct

Derivative Transactions

Date	Security	Exercise Price	Code	Shares	A/D	Expiration	Underlying	Ownership
2019-07-29	Series A Preferred Stock	$	C	19524	Disposed		Common Stock (16015)	Indirect
2019-07-29	Series B Preferred Stock	$	C	122158	Disposed		Common Stock (100210)	Direct
2019-07-29	Series D Preferred Stock	$	C	15918	Disposed		Common Stock (13058)	Direct
2019-07-29	Series D Preferred Stock	$	C	337754	Disposed		Common Stock (277074)	Indirect
2019-07-29	Series E-1 Preferred Stock	$	C	463453	Disposed		Common Stock (380190)	Indirect
2019-07-29	Series E-2 Preferred Stock	$	C	5461	Disposed		Common Stock (4479)	Direct
2019-07-29	Series E-2 Preferred Stock	$	C	158379	Disposed		Common Stock (129925)	Indirect
2019-07-29	Series E-3 Preferred Stock	$	C	4681	Disposed		Common Stock (3840)	Direct
2019-07-29	Series E-3 Preferred Stock	$	C	142843	Disposed		Common Stock (117180)	Indirect
2019-07-29	Series F Preferred Stock	$	C	57899	Disposed		Common Stock (47495)	Direct
2019-07-29	Series F Preferred Stock	$	C	507762	Disposed		Common Stock (416537)	Indirect
2019-07-29	Convertible Promissory Note	$12.80	C		Disposed		Common Stock (16722)	Direct
2019-07-29	Convertible Promissory Note	$12.80	C		Disposed		Common Stock (97428)	Indirect

Footnotes

F1: The shares of Common Stock issued upon conversion of the Preferred Stock were calculated by first aggregating all series of Preferred Stock
held by the Reporting Person, in accordance with the terms of the Company's then-effective Certificate of Incorporation.

F2: Every 1.219 outstanding shares of Preferred Stock automatically converted into 1 share of Common Stock immediately prior to the closing of the Issuer's initial public offering (the "IPO"), for no additional consideration, with cash paid for any fractional shares. The Preferred Stock had no expiration date.

F3: Held by MGC Venture Partners 2013, L.P. ("MGC 2013 LP"). MGC Venture Partners 2013 GP, LLC ("MGC 2013 GP") is the general partner of MGC 2013 LP.

F4: The Reporting Person is a managing director of MGC 2013 GP and a managing partner of MGC Venture Partners 2018 GP, LLC ("MGC 2018 GP"), and shares voting and investment power over the shares held by MGC 2013 LP, MGC Venture Partners 2018, L.P. ("MGC 2018 LP") and MGC Venture Partners QP 2018, L.P. ("MGC QP 2018 LP"). The Reporting Person disclaims beneficial ownership of the shares held by MGC 2013 GP, MGC 2018 GP, MGC 2013 LP, MGC 2018 LP and MGC QP 2018 LP as reported herein, except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that the Reporting Person is the beneficial owners of such securities for purposes of Section 16 or for any other purposes.

F5: The principal amount of the Convertible Promissory Note held by the designated Reporting Person was $1,200,000.00. Upon closing of the IPO, all unpaid principal and accrued interest outstanding on the Convertible Promissory Note (the "Conversion Amount") automatically converted into the number of shares of Common Stock equal to the Conversion Amount as of the date immediately prior to the closing date divided by 80% of the IPO price per share of $16.00 per share.

F6: Represents a purchase from the underwriters in the Issuer's IPO.

F7: Held by MGC 2013 LP, MGC 2018 LP and MGC QP 2018 LP. MGC 2018 GP is the general partner of MGC 2018 LP and MGC QP 2018 LP.

F8: The principal amount of the Convertible Promissory Note held by the designated Reporting Person was $205,970.51. Upon closing of the IPO, the Conversion Amount automatically converted into the number of shares of Common Stock equal to the Conversion Amount as of the date immediately prior to the closing date divided by 80% of the IPO price per share of $16.00 per share.