Timothy B. Lowinger - May 20, 2021 Form 4 Insider Report for Mersana Therapeutics, Inc. (MRSN)

Role
Chief Science & Tech. Officer
Signature
/s/ Brian DeSchuytner, as Attorney-in-Fact
Stock symbol
MRSN
Transactions as of
May 20, 2021
Transactions value $
-$37,539
Form type
4
Date filed
5/24/2021, 04:30 PM
Next filing
Jun 23, 2021

Transactions Table

Type Sym Class Transaction Value $ Shares Change % * Price $ Shares After Date Ownership Footnotes
transaction MRSN Common Stock Options Exercise $6.58K +1.88K +5.96% $3.51 33.3K May 20, 2021 Direct F1
transaction MRSN Common Stock Sale -$26.4K -1.88K -5.63% $14.10* 31.4K May 20, 2021 Direct F1, F2
transaction MRSN Common Stock Options Exercise $13.7K +2.23K +7.08% $6.16 33.7K May 20, 2021 Direct F1
transaction MRSN Common Stock Sale -$31.4K -2.23K -6.61% $14.10* 31.4K May 20, 2021 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 MRSN Stock Option (right to buy) Options Exercise $0 -1.88K -13.34% $0.00 12.2K May 20, 2021 Common Stock 1.88K $3.51 Direct F1, F3
transaction MRSN Stock Option (right to buy) Options Exercise $0 -2.23K -2.59% $0.00 83.9K May 20, 2021 Common Stock 2.23K $6.16 Direct F1, F4
* 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 This price is a weighted average price. These shares were sold in multiple transactions at prices ranging from $13.89 to $14.34, inclusive. The reporting person undertakes to provide to Mersana Therapeutics, Inc., any other security holder of Mersana Therapeutics Inc. or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the ranges set forth in this footnote.
F3 The option vests in equal quarterly installments over the first four years after the vesting commencement date, January 23, 2019.
F4 The option vests in equal quarterly installments over the first four years after the vesting commencement date, January 15, 2020.