Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share (YMAB)

Q: What does CUSIP 984241109 represent in this 13F holders report?

CUSIP 984241109 is the security identifier for YMAB - Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share used to aggregate holder disclosures.

Q: How many institutions held YMAB - Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share in Q1 2021?

116 institutional investors reported YMAB - Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share for Q1 2021. Use the holders table for investor-level position and value details.

CUSIP: 984241109

Q1 2021 13F Holders as of 31 Mar 2021

Type / Class: Equity / Common Stock, $0.0001 par value per share
Shares outstanding: 45,101,565
Total 13F shares: 26,332,523
Share change: +4,095,922
Total reported value: $796,209,961
Price per share: $30.24
Number of holders: 116
Value change: +$116,007,549
Number of buys: 72
Number of sells: 44

Quarterly Holders Quick Answers

What is CUSIP 984241109?
CUSIP 984241109 identifies YMAB - Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share in SEC institutional holdings data.

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Explore More Reporting Periods

Jump to adjacent filing periods for faster comparison and easier crawl discovery.

Newer quarter: Q2 2021
Previous quarter: Q4 2020

Recent filing periods for CUSIP 984241109:

Q4 2025 Q3 2025 Q2 2025 Q1 2025 Q4 2024 Q3 2024 Q2 2024 Q1 2024

Top shareholders of YMAB - Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share (13F + 13D/G + 3/4/5)

Grouped by holder across the latest SEC ownership disclosures. Ownership % is shown only when it is directly reported or safely comparable across share classes.

Methodology: rows are grouped by holder and ranked by the holder's primary source value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.

No top shareholder records were found across 13F, 13D/G, and Forms 3/4/5 for this issuer.

Institutional Holders of Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share (YMAB) as of Q1 2021

As of 31 Mar 2021, Y-mAbs Therapeutics, Inc. - Common Stock, $0.0001 par value per share (YMAB) was held by 116 institutional shareholders that filed Form 13F with the SEC. Together, they reported ownership of 26,332,523 shares. The largest 10 holders included WELLINGTON MANAGEMENT GROUP LLP, BlackRock Inc., Sofinnova Investments, Inc., STATE STREET CORP, VANGUARD GROUP INC, FMR LLC, Artisan Partners Limited Partnership, ALLIANCEBERNSTEIN L.P., Cormorant Asset Management, LP, and First Light Asset Management, LLC. This page lists 116 institutional shareholders reporting positions in this security for the Q1 2021 filing period.

Investor	Option	Weight %	Change %	Value $	* Price	Shares	Share Change	Activity	Report Period

Compare Q1 2021 vs Q4 2020 Across Filers

Q4 2020 holders

115

Q1 2021 holders

116

Holder diff

Investor	Q4 2020 Shares	Q1 2021 Shares	Share Diff	Share Chg %	Q4 2020 Value $	Q1 2021 Value $	Value Diff $	Value Chg %

Trend: ostatnie 8 kwartałów (+ wybrane okresy porównania).

Quarterly Holders Trend

Quarterly Value Trend

Quarterly Shares Trend

* Reported Price is the price of the security as of the portfolio date. This value is significant in that it is the last known price at which the security was still held.
An asterisk sign (*) next to the price indicates that the price is likely invalid.