Timothy B. Lowinger - Jul 1, 2021 Form 4 Insider Report for Mersana Therapeutics, Inc. (MRSN)

Role
CS & Technology Officer
Signature
/s/ Brian DeSchuytner, as Attorney-in-Fact
Stock symbol
MRSN
Transactions as of
Jul 1, 2021
Transactions value $
-$19,006
Form type
4
Date filed
7/2/2021, 04:32 PM
Previous filing
Jun 23, 2021
Next filing
Jul 9, 2021

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MRSN Common Stock Options Exercise $6.59K +1.88K +5.97% $3.51 33.3K Jul 1, 2021 Direct F1
transaction MRSN Common Stock Options Exercise $55.40 +9 +0.03% $6.16 33.3K Jul 1, 2021 Direct F1
transaction MRSN Common Stock Sale -$25.6K -1.89K -5.66% $13.60* 31.4K Jul 1, 2021 Direct F1

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 MRSN Stock Option (right to buy) Options Exercise $0 -1.88K -15.41% $0.00 10.3K Jul 1, 2021 Common Stock 1.88K $3.51 Direct F1, F2
transaction MRSN Stock Option (right to buy) Options Exercise $0 -9 -0.01% $0.00 81.6K Jul 1, 2021 Common Stock 9 $6.16 Direct F1, F3
* An asterisk sign (*) next to the price indicates that the price is likely invalid.

Explanation of Responses:

Id Content
F1 Transaction effected pursuant to a Rule 10b5-1 trading plan adopted by the reporting person on August 12, 2020.
F2 The option vests in equal quarterly installments over the first four years after the vesting commencement date, January 23, 2019.
F3 The option vests in equal quarterly installments over the first four years after the vesting commencement date, January 15, 2020.