PROTOPAPAS ANNA (President & CEO) sold 19.0% of their position (29.40K shares) of MERSANA THERAPEUTICS, INC. on the open market

Open‑market sale worth $79.7K — a significant reduction. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 1 sale

PROTOPAPAS ANNA

Filed: 1/17/2024ACC: 0001104659-24-004551

InsiderPROTOPAPAS ANNACIK 1347582

→

IssuerMERSANA THERAPEUTICS, INC.CIK 1442836

DirectorOfficer· President & CEO

Since Jan 2019

-29.40K

Net shares

Net seller

$79.7K

Total sold

Open market trades

0B · 1S

Total transactions

86.96K acquired · 116.36K disposed

Non-Derivative Transactions5

Common Stock

Direct

M · Option Exercise

+31.25K

Price / share

—

Trade value

—

% of position

46.2%

1/13/2024

67.59K→98.84K

Common Stock

Direct

M · Option Exercise

+16.75K

Price / share

—

Trade value

—

% of position

16.9%

1/14/2024

98.84K→115.59K

Common Stock

Direct

M · Option Exercise

+21.25K

Price / share

—

Trade value

—

% of position

18.4%

1/15/2024

115.59K→136.84K

Common Stock

Direct

M · Option Exercise

+17.71K

Price / share

—

Trade value

—

% of position

12.9%

1/15/2024

136.84K→154.55K

Common Stock

Direct

S · Sale

−29.40K

Price / share

$2.71

Trade value

$79.67K

% of position

19.0%

1/16/2024

154.55K→125.15K

Total

Net shares

+57.56K

Net value

-$79.67K

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Common Stock Direct	1/13/2024	M · Option Exercise	+31.25K	—	—	46.2%	67.59K	98.84K
Common Stock Direct	1/14/2024	M · Option Exercise	+16.75K	—	—	16.9%	98.84K	115.59K
Common Stock Direct	1/15/2024	M · Option Exercise	+21.25K	—	—	18.4%	115.59K	136.84K
Common Stock Direct	1/15/2024	M · Option Exercise	+17.71K	—	—	12.9%	136.84K	154.55K
Common Stock Direct	1/16/2024	S · Sale	−29.40K	$2.71	$79.67K	19.0%	154.55K	125.15K
Total			+57.56K		-$79.67K

Derivative Transactions4

Restricted Stock Unit

Direct

M · Option Exercise

Converts to

Common Stock

31.25K shares

−31.25K

Strike price

Held after

93.75K

Exercisable

—

1/13/2024

Restricted Stock Unit

Direct

M · Option Exercise

Converts to

Common Stock

16.75K shares

−16.75K

Strike price

Held after

33.50K

Exercisable

—

1/14/2024

Restricted Stock Unit

Direct

M · Option Exercise

Converts to

Common Stock

21.25K shares

−21.25K

Strike price

Held after

21.25K

Exercisable

—

1/15/2024

Restricted Stock Unit

Direct

M · Option Exercise

Converts to

Common Stock

17.71K shares

−17.71K

Strike price

Held after

0.00

Exercisable

—

1/15/2024

Security	Converts To	Date	Type	Shares	Exercisable	Held After
Restricted Stock Unit Direct	Common Stock31.25K shares	1/13/2024	M · Option Exercise	−31.25K	—	93.75K
Restricted Stock Unit Direct	Common Stock16.75K shares	1/14/2024	M · Option Exercise	−16.75K	—	33.50K
Restricted Stock Unit Direct	Common Stock21.25K shares	1/15/2024	M · Option Exercise	−21.25K	—	21.25K
Restricted Stock Unit Direct	Common Stock17.71K shares	1/15/2024	M · Option Exercise	−17.71K	—	0.00

Non-Derivative Holdings (Post-Transaction)2

Common Stock

Indirect

Shares owned240.24K

Common Stock

Indirect

Shares owned72.26K

Total

312.51K indirect312.51K

Security Title	Shares Owned	Ownership Type
Common Stock	240.24K	Indirect
Common Stock	72.26K	Indirect
Total	312.51K	312.51K indirect

Derivative Holdings (Post-Transaction)0

No derivative holdings reported