Alector, Inc.

ALEC • NASDAQ

Alector, Inc. is a biotechnology company in the healthcare sector on NASDAQ, led by Arnon Rosenthal, with a market cap of $162.6M. As of Q3 2025, 74% of shares are held by 148 institutional investors, with FMR LLC as the largest holder at 15.0%.

Chief Executive OfficerArnon Rosenthal

Market Cap$162.6M

Biotechnology

Healthcare

Employees244.0

Websitealector.com

Country

United States of America

Overview

Overview of institutional ownership in ALEC as of Q3 2025 with a market cap of $299.6M

All Institutions

Institutions: 148
Value Held: $221.3M
Shares Held: 74.8M
Avg Position: $1.5M
Median Position: $147.4K

Hedge Funds

Hedge Funds: 22
Value Held: $56.8M
Shares Held: 19.2M
Avg Position: $2.6M
Median Position: $1.9M

Ownership Breakdown

Institutional (non-HF)

54.9%

$164.5M

Hedge Funds

18.95%

$56.8M

Retail & Other

26.14%

$78.3M

Based on market cap of $299.6M as of Q3 2025. Institutional (non-HF) excludes hedge funds to avoid double counting.

Biggest Investors

Institutions with the largest positions in ALEC as of Q3 2025

Institution	Key People	Position Value	Ownership	Owned Since	Total AUM (Long)
FMR LLC Institution	-	$44.9M 0.00% of portfolio	15.00% 15.2M shares	Q1 2019 Held for 6y 8m	$1.92T
B BlackRock, Inc. Institution	-	$21.3M 0.00% of portfolio	7.11% 7.2M shares	Q1 2019 Held for 6y 8m	$5.67T
RTW INVESTMENTS, LLC Hedge Fund•Sector	Peter M Fong President	$20.7M 0.26% of portfolio	6.91% 7.0M shares	Q3 2025 Held for 2 months	$8.1B
VANGUARD GROUP INC Institution	Salim Ramji CEO	$17.9M 0.00% of portfolio	5.96% 6.0M shares	Q1 2019 Held for 6y 8m	$6.69T
Merck & Co., Inc. Institution	Robert M. Davis CEO	$10.5M 4.82% of portfolio	3.50% 3.5M shares	Q4 2024 Held for 11 months	$217.8M
ACADIAN ASSET MANAGEMENT LLC Long Only Manager	Gillian Morna Therese Savage CEO	$7.0M 0.01% of portfolio	2.34% 2.4M shares	Q4 2021 Held for 3y 11m	$51.5B
PRICE T ROWE ASSOCIATES INC /MD/ Long Only Manager	Robert W Sharps President	$6.5M 0.00% of portfolio	2.16% 2.2M shares	Q3 2019 Held for 6y 2m	$912.31B
GEODE CAPITAL MANAGEMENT LLC ETF Provider	David Kenneth Lane CEO	$5.5M 0.00% of portfolio	1.84% 1.9M shares	Q1 2019 Held for 6y 8m	$1.57T
STATE STREET CORP Institution	Ronald P. O'Hanley CEO	$5.1M 0.00% of portfolio	1.71% 1.7M shares	Q1 2019 Held for 6y 8m	$2.88T
Eversept Partners, LLC Hedge Fund•Long/Short	Rishi Rasesh Shah President	$4.4M 0.34% of portfolio	1.47% 1.5M shares	Q1 2024 Held for 1y 8m	$1.3B

Net Capital Flow

Institutional buying and selling activity for ALEC in Q3 2025

Traded: +$17.9M
Buyers: 71
Sellers: 51
Total Bought: +$40.5M
Total Sold: −$22.6M
Avg Position: $1.4M

Biggest Buyers

Institution	Net Bought	Current Position
RTW INVESTMENTS, LLC Hedge Fund•Sector	+$20.7M +7.0M shares	$20.7M 7.0M shares
6 683 Capital Management, LLC Hedge Fund•Long/Short	+$3.0M +1.0M shares	$3.0M 1.0M shares
MILLENNIUM MANAGEMENT LLC Hedge Fund•Multi-Strategy	+$2.2M +744.2K shares	$3.4M 1.2M shares
BARCLAYS PLC Institution	+$2.1M +703.6K shares	$2.6M 873.4K shares
D D. E. Shaw & Co., Inc. Institution	+$1.3M +444.0K shares	$2.9M 978.2K shares
J JANE STREET GROUP, LLC Institution	+$965.8K +326.3K shares	$1.0M 350.2K shares
M MEDICI CAPITAL LLC Institution	+$931.8K +314.8K shares	$1.4M 482.0K shares
R ROYAL BANK OF CANADA Institution	+$773.9K +261.5K shares	$1.9M 628.7K shares
AMERIPRISE FINANCIAL INC Institution	+$769.3K +259.9K shares	$811.2K 274.0K shares
GOLDMAN SACHS GROUP INC Institution	+$696.9K +235.4K shares	$1.8M 609.9K shares

Biggest Sellers

Institution	Net Sold	Current Position
PRICE T ROWE ASSOCIATES INC /MD/ Long Only Manager	−$8.0M −2.7M shares	$6.5M 2.2M shares
A ADAR1 Capital Management, LLC Hedge Fund•Long/Short	−$2.4M −1.7M shares	Sold Off 0 shares
B BlackRock, Inc. Institution	−$2.3M −775.6K shares	$21.3M 7.2M shares
Eversept Partners, LLC Hedge Fund•Long/Short	−$1.5M −497.3K shares	$4.4M 1.5M shares
Sio Capital Management, LLC Hedge Fund•Long/Short	−$1.2M −845.5K shares	Sold Off 0 shares
T TD ASSET MANAGEMENT INC Institution	−$1.1M −378.0K shares	$810.3K 273.7K shares
RENAISSANCE TECHNOLOGIES LLC Hedge Fund•Quant	−$904.9K −305.7K shares	$2.8M 949.2K shares
MORGAN STANLEY RIA/Wealth	−$510.3K −172.4K shares	$1.3M 434.2K shares
Ikarian Capital, LLC Hedge Fund•Event Driven	−$414.4K −140.0K shares	$2.2M 760.0K shares
DIADEMA PARTNERS LP Hedge Fund•Long/Short	−$384.8K −130.0K shares	$402.6K 136.0K shares

Entry and Exit Activity

Institutions that initiated new positions or completely exited ALEC in Q3 2025

New Positions: 8
New Value: $23.8M
Exited Positions: 12
Exited Value: $4.7M

New Positions

Institution	Position Value
RTW INVESTMENTS, LLC Hedge Fund•Sector	$20.7M 7.0M shares
6 683 Capital Management, LLC Hedge Fund•Long/Short	$3.0M 1.0M shares
Savant Capital, LLC RIA/Wealth	$34.6K 11.7K shares
HBK Sorce Advisory LLC Hedge Fund•Multi-Strategy	$34.4K 11.2K shares
SVB Capital Management, LLC Fund of Funds	$30.4K 10.3K shares
Lexington Partners L.P. Private Equity	$29.9K 10.1K shares
O Optiver Holding B.V. Institution	$3.0K 1.0K shares
Efficient Wealth Management LLC RIA/Wealth	- 336.0 shares

Exited Positions

Institution	Previous Position
A ADAR1 Capital Management, LLC Hedge Fund•Long/Short	$2.4M 1.7M shares
Sio Capital Management, LLC Hedge Fund•Long/Short	$1.2M 845.5K shares
Walleye Trading Advisors, LLC Hedge Fund•Multi-Strategy	$372.7K 266.2K shares
S State of Wyoming Institution	$312.3K 223.1K shares
GSA CAPITAL PARTNERS LLP Hedge Fund•Quant	$210.9K 150.7K shares
SUSQUEHANNA FUNDAMENTAL INVESTMENTS, LLC Hedge Fund•Distressed	$99.1K 70.8K shares
ALGERT COLDIRON INVESTORS LLC Hedge Fund•Quant	$62.2K 44.5K shares
S STATE BOARD OF ADMINISTRATION OF FLORIDA RETIREMENT SYSTEM Institution	$35.8K 25.6K shares
S SHELL ASSET MANAGEMENT CO Institution	$19.4K 13.9K shares
$US BANCORP \DE\ logo$ US BANCORP \DE\ Institution	$17.4K 12.4K shares

Options Activity

Institutions with the largest Call and Put options positions in ALEC as of Q3 2025

Call Positions: 4
Call Value: $1.8M
Put Positions: 3
Put Value: $659.2K

Call Positions

Institution	Position Value
Logos Global Management LP Hedge Fund•Long/Short	$1.5M 5.0K contracts
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity	$248.9K 841.0 contracts
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy	$49.7K 168.0 contracts
Point72 Asset Management, L.P. Hedge Fund•Multi-Strategy	$37.6K 127.0 contracts

Put Positions

Institution	Position Value
SUSQUEHANNA INTERNATIONAL GROUP, LLP Private Equity	$432.5K 1.5K contracts
CITADEL ADVISORS LLC Hedge Fund•Multi-Strategy	$189.1K 639.0 contracts
Point72 Asset Management, L.P. Hedge Fund•Multi-Strategy	$37.6K 127.0 contracts

Most Committed Institutions

Institutions with ALEC as the highest % of their portfolio as of Q3 2025

Institution	Key People	Portfolio Weight	Ownership	Owned Since	Total AUM (Long)
Merck & Co., Inc. Institution	Robert M. Davis CEO	4.82% $10.5M	3.50% 3.5M shares	Q4 2024 Held for 11 months	$217.8M
New Leaf Venture Partners, L.L.C. Venture Capital	Vijay Kiran Lathi Managing Partner	2.33% $1.0M	0.34% 339.6K shares	Q1 2019 Held for 6y 8m	$43.0M
M MEDICI CAPITAL LLC Institution	-	1.83% $1.4M	0.48% 482.0K shares	Q4 2022 Held for 2y 11m	$78.1M
E Euclidean Capital LLC Institution	-	1.63% $3.9M	1.29% 1.3M shares	Q4 2020 Held for 4y 11m	$238.0M
5 5AM Venture Management, LLC Institution	-	1.08% $2.9M	0.98% 995.8K shares	Q4 2024 Held for 11 months	$273.0M
D DAFNA Capital Management LLC Hedge Fund•Event Driven	Nathan Fischel CEO	0.59% $2.4M	0.79% 798.4K shares	Q1 2019 Held for 6y 8m	$397.7M
Ikarian Capital, LLC Hedge Fund•Event Driven	Neil Tristan Shahrestani CEO	0.46% $2.2M	0.75% 760.0K shares	Q4 2024 Held for 11 months	$494.3M
Eversept Partners, LLC Hedge Fund•Long/Short	Rishi Rasesh Shah President	0.34% $4.4M	1.47% 1.5M shares	Q1 2024 Held for 1y 8m	$1.3B
DIADEMA PARTNERS LP Hedge Fund•Long/Short	Timothy Beau Bassett CIO	0.28% $402.6K	0.13% 136.0K shares	Q4 2024 Held for 11 months	$143.3M
6 683 Capital Management, LLC Hedge Fund•Long/Short	Ari Jonathan Zweiman Managing Partner	0.28% $3.0M	0.99% 1.0M shares	Q3 2025 Held for 2 months	$1.1B

Hedge Fund Spotlight

Discover hedge funds investing in ALEC

Artia Global Partners LP

Hedge Fund • Long/Short

Portfolio ManagerOnusa Nmn Chantanapongwanij

Portfolio Value: $568.3M
Positions: 48
Last Reported: Q3 2025

Sector Allocation

Position in Alector, Inc.

Market Value: $210.2K
Shares Held: 71.0K
Portfolio Weight: 0.04%
Owned Since: 2025-Q3

Top Holding	Sector	Market Value	Weight
1 Insmed INSM	Biotechnology Healthcare	$105.4M	18.55%
2 ARGX argenx ARGX	Unknown Unknown	$57.8M	10.16%
3 Soleno Therapeutics SLNO	Biotechnology Healthcare	$45.4M	8.00%

View full profile

Alector, Inc.

Overview

All Institutions

Hedge Funds

Ownership Breakdown

Biggest Investors

Net Capital Flow

Biggest Buyers

Biggest Sellers

Entry and Exit Activity

New Positions

Exited Positions

Options Activity

Call Positions

Put Positions

Most Committed Institutions

Hedge Fund Spotlight

Position in Alector, Inc.

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