Security key
59045L106
Mersana Therapeutics, Inc. - Common Stock, par value $0.0001 per share (MRSN)
CUSIP: 59045L106
Q1 2020 13F Holders as of 31 Mar 2020
- Security type / class
- Equity / Common Stock, par value $0.0001 per share
- Total 13F shares
- 40,118,913
- Total 13F value
- $233,891,407
- Share change
- +4,460,347
- SEC-reported price per share
- $5.83
- Number of holders
- 82
- Value change
- +$26,078,897
- Number of buys
- 54
- Number of sells
- 23
- Shares outstanding
- 4,992,318
Holder snapshot
6 signals
Security identity
Names, identifiers, and filing context for this profile.
1 source field
Report period
Q1 2020
Institutions
82
Top holders
10
MRSN full security history
Ownership snapshot
Full 13F holder table
Newer quarter: Q4 2025
Mersana Therapeutics, Inc. SEC filings
Mersana Therapeutics, Inc. company facts
Broader feeds
Reporting periods
Holder history for CUSIP 59045L106
Recent filing periods:
Ownership snapshot
Top reported holders of MRSN - Mersana Therapeutics, Inc. - Common Stock, par value $0.0001 per share (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
NEA Management Company, LLC
Disclosed value leader
NEA Management Company, LLC
Comparable rows
15/15
Latest evidence
31 Dec 2019
13F
Lead comparable stake: 240%
Showing 1-6 of 15 holder rows.
Quick read
NEA Management Company, LLC leads the comparable SEC ownership view at 240%.
15 of 15 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens NEA Management Company, LLC's linked filing trail.
Comparable ownership
Top 5
NEA Management Company, LLC
240%
Sarissa Capital Management LP
75%
BlackRock Finance, Inc.
49%
ORBIMED ADVISORS LLC
42%
VANGUARD GROUP INC
37%
Ownership % is shown only when SEC disclosures are safely comparable across share classes.
Detailed SEC evidence table Showing 1-6 of 15 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| NEA Management Company, LLC |
13F
Company
|
240%
|
$68,552,000
11,963,649 shares
|
— | 31 Dec 2019 |
| Sarissa Capital Management LP |
13F
Company
|
75%
|
$21,487,000
3,750,000 shares
|
— | 31 Dec 2019 |
| BlackRock Finance, Inc. |
13F
Company
|
49%
|
$14,126,000
2,465,319 shares
|
— | 31 Dec 2019 |
| ORBIMED ADVISORS LLC |
13F
Company
|
42%
|
$11,880,000
2,073,319 shares
|
— | 31 Dec 2019 |
| VANGUARD GROUP INC |
13F
Company
|
37%
|
$10,699,000
1,867,264 shares
|
— | 31 Dec 2019 |
| VHCP Management III, LLC |
13F
Company
|
31%
|
$8,947,000
1,561,389 shares
|
— | 31 Dec 2019 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
13F holder rows
Institutional holders as of Q1 2020
Investor-level positions for this CUSIP, loaded as an interactive table.
Institutions
82
Shares
40,118,913
Rows available
82
| Investor | Option | Weight % | Change % | SEC-reported value | * Price | Shares | Share Change | Activity | Report Period |
|---|
* SEC-reported price is the security price as of the portfolio date and can indicate the last known price at which the security was still held. The marker flags a reported price that did not pass the local price check.
Compare Q1 2020 vs Q4 2025 Across Filers
Q4 2025 holders
3
Q1 2020 holders
82
Holder diff
79
| Investor | Q4 2025 Shares | Q1 2020 Shares | Share Diff | Share Chg % | Q4 2025 value | Q1 2020 value | Value change | Value Chg % |
|---|
Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).
Quarterly Holders Trend
Quarterly Value Trend
Quarterly Shares Trend