Mariner, LLC

SEC CIK: 0001373442
Latest filing: Aug 13, 2026

SEC filings (opens in a new tab)

UPB holding history

Upstream Bio, Inc. in every 13F filed by Mariner, LLC, including the quarters it was sold out or no filing was made. Changes compare share counts with the previous calendar quarter.

UPB overview All 13F holders of UPB Full Q2 2026 holdings

Shares (Q2 2026): 33,141
Value: $229.3K
% of portfolio: <0.1%
Quarters held: 4; Since Q3 2025

Holdings of UPB by Mariner, LLC, by quarter
Quarter	Shares	Value	% of portfolio	Share change	Action	All holders
Q2 2026	33,141	$229.3K	<0.1%	+5,827+21.3%	Added	Holders
Q1 2026	27,314	$245.8K	<0.1%	+15,484+130.9%	Added	Holders
Q4 2025	11,830	$321.2K	<0.1%	+897+8.2%	Added	Holders
Q3 2025	10,933	$205.7K	<0.1%	+10,933	New	Holders