Vault-13

ARCELLX INC ACLX

COMMON STOCK · Common Stock · CUSIP 03940C100

168 institutional holders -16 vs Q1 2024
51,314,91751.3m shares reported held*
$2.8bnreported value*
20 new 79 added 50 reduced 36 sold out net bought ≈ $60.8m (+1.1m shares)

* Summed across managers. Shares that two managers' reports both contain – a subsidiary's holdings that its parent's report includes too, or a sub-adviser's in its client's – are counted once ($3.7m this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $55.19. Options: 5 managers hold calls ($6.8m notional), 4 hold puts ($3.1m).

Trends to Q2 2024

Institutional holders

Managers reporting a position, each quarter

0100200Q3 22: 74Q4 22: 127Q1 23: 119Q2 23: 140Q3 23: 138Q4 23: 158Q1 24: 184Q2 24: 168168Q3 22Q1 23Q3 23Q1 24Q2 24
Numbers
QuarterHolders
Q3 202274
Q4 2022127
Q1 2023119
Q2 2023140
Q3 2023138
Q4 2023158
Q1 2024184
Q2 2024168

Buyers vs sellers

Managers adding to or starting a position, vs cutting or selling out

Bought or addedCut or sold out
2000200Q4 22: 86 bought or addedQ4 22: 32 cut or sold outQ4 22Q1 23: 61 bought or addedQ1 23: 63 cut or sold outQ2 23: 99 bought or addedQ2 23: 44 cut or sold outQ2 23Q3 23: 75 bought or addedQ3 23: 57 cut or sold outQ4 23: 85 bought or addedQ4 23: 64 cut or sold outQ4 23Q1 24: 108 bought or addedQ1 24: 73 cut or sold outQ2 24: 99 bought or addedQ2 24: 86 cut or sold outQ2 24
Numbers
QuarterBought or addedCut or sold out
Q4 20228632
Q1 20236163
Q2 20239944
Q3 20237557
Q4 20238564
Q1 202410873
Q2 20249986

Calls vs puts

Options held, notional value, last 4 quarters. P/C = puts ÷ calls

CallsPuts
$0$10m$20m$30mQ3 23 calls: $846.8kQ3 23 puts: $190.2kQ3 23P/C 0.22Q4 23 calls: $22.5mQ4 23 puts: $8.7mQ4 23P/C 0.38Q1 24 calls: $5.5mQ1 24 puts: $13.1mQ1 24P/C 2.36Q2 24 calls: $6.8mQ2 24 puts: $3.1mQ2 24P/C 0.45
Numbers
QuarterCallsPutsP/C
Q3 2023$846.8k$190.2k0.22
Q4 2023$22.5m$8.7m0.38
Q1 2024$5.5m$13.1m2.36
Q2 2024$6.8m$3.1m0.45

Biggest buyers

RA CAPITAL MANAGEMENT, L.P. New +1,604,014+1.6m
FMR LLC Added +1,092,839+1.1m
Vestal Point Capital, LP Added +575,000+575.0k
BlackRock Inc. Added +450,296+450.3k
JANUS HENDERSON GROUP PLC Added +380,309+380.3k
PRICE T ROWE ASSOCIATES INC /MD/ Added +286,137+286.1k
GREAT POINT PARTNERS LLC Added +192,000+192.0k
T. Rowe Price Investment Management, Inc. Added +190,929+190.9k
Affinity Asset Advisors, LLC Added +160,000+160.0k
STEMPOINT CAPITAL LP Added +140,442+140.4k

Biggest sellers

MORGAN STANLEY Reduced -1,545,209-1.5m
LORD, ABBETT & CO. LLC Reduced -648,546-648.5k
JPMORGAN CHASE & CO Reduced -580,782-580.8k
Cormorant Asset Management, LP Reduced -255,000-255.0k
FEDERATED HERMES, INC. Reduced -225,928-225.9k
VOYA INVESTMENT MANAGEMENT LLC Reduced -164,271-164.3k
TWO SIGMA INVESTMENTS, LP Reduced -154,393-154.4k
STATE STREET CORP Reduced -129,454-129.5k
VOLORIDGE INVESTMENT MANAGEMENT, LLC Reduced -128,365-128.4k
BANK OF AMERICA CORP /DE/ Reduced -111,135-111.1k

Biggest calls

JPMORGAN CHASE & CO New $3.0m54.2k shares
SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced $1.8m32.7k shares
CITADEL ADVISORS LLC Added $1.2m20.9k shares
GROUP ONE TRADING LLC New $838.9k15.2k shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 shares

Biggest puts

SUSQUEHANNA INTERNATIONAL GROUP, LLP Reduced $2.8m51.6k shares
CITADEL ADVISORS LLC Reduced $115.9k2.1k shares
GROUP ONE TRADING LLC Added $110.4k2.0k shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 shares

Options at notional value: the value of the shares the contracts control, as filers report them, not what the options cost. Not included in the holders, shares or buying above.

Major shareholders (over 5%)

Anyone who owns more than 5% of a class of the company's shares has to say so: on Schedule 13D if they may try to influence or control the company, on 13G if they're a passive investor, and update it as the stake changes. Each holder's latest filing, from 19 Dec 2024 on; percentages are of the share class, as the holder worked them out.

HolderStakeChangeShares Last filed
GILEAD SCIENCES, INC. 13D · may seek influence +88.5 pts · filed 2026-04-28
Stated purposeItem 4 of the Original Schedule 13D is amended to include the following at the end thereof: "As previously disclosed, Gilead, Purchaser and Arcellx entered into the Merger Agreement pursuant to which Purchaser commenced the Offer on March 6, 2026. The Offer expired at 5:00 p.m., Eastern Time, on April 27, 2026. Computershare Trust Company N.A., the depositary and paying agent for the Offer, advised Gilead that, as of the expiration of the Offer, 38,795,604 Shares had been validly tendered and not validly withdrawn pursuant to the Offer, representing, together with Shares already owned by Gilead, approximately 77.2% of the Shares outstanding as of the expiration of the Offer. Following consummation of the Offer, on April 28, 2026, Gilead completed its acquisition of Arcellx through the m… Full filing
 100.0% +88.5 pts 100 2026-04-28
BlackRock, Inc. 13G · institution filed 2025-04-17 6.4% 3.5m 2025-04-17

Fell to 5% or below in the last year: Paradigm Biocapital Advisors LP (0.0%, 2026-08-14), Vestal Point Capital, LP (0.0%, 2026-05-15), New Enterprise Associates 15, L.P. (0.0%, 2026-04-30), Elghandour Rami (0.0%, 2026-04-28), VANGUARD GROUP INC (0.0%, 2026-03-26), T. Rowe Price Investment Management, Inc. (4.5%, 2026-03-06), FMR LLC (0.5%, 2026-03-06), RA CAPITAL MANAGEMENT, L.P. (2.2%, 2026-02-17)

Holders, Q2 2024

#ManagerLocationShares Value% of their portfolioChangeShares change
1 FMR LLC 0.02% of their portfolio BOSTON, MA 6,487,3346.5m $358.0m $358.0m 0.02% Added +1.1m +1,092,839
2 PERCEPTIVE ADVISORS LLC 5.18% of their portfolio NEW YORK, NY 3,889,7393.9m $214.7m $214.7m 5.18% Reduced -43.8k -43,817
3 Paradigm Biocapital Advisors LP 8.13% of their portfolio NEW YORK, NY 3,848,0953.8m $212.4m $212.4m 8.13% Added +30.0k +30,000
4 NEA Management Company, LLC 15.55% of their portfolio TIMONIUM, MD 3,745,2623.7m $206.7m $206.7m 15.55% Unchanged
5 BlackRock Inc. 0.00% of their portfolio New York, NY 3,516,3643.5m $194.1m $194.1m 0.00% Added +450.3k +450,296
6 SR One Capital Management, LP 40.55% of their portfolio Redwood City, CA 2,346,6302.3m $129.5m $129.5m 40.55% Unchanged
7 VANGUARD GROUP INC 0.00% of their portfolio Valley Forge, PA 2,296,1952.3m $126.7m $126.7m 0.00% Added +67.3k +67,339
8 JANUS HENDERSON GROUP PLC 0.06% of their portfolio LONDON, X0 1,902,6181.9m $105.0m $105.0m 0.06% Added +380.3k +380,309
9 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 1,755,6641.8m $96.9m $96.9m 0.00% Reduced -129.5k -129,454
10 LORD, ABBETT & CO. LLC 0.16% of their portfolio JERSEY CITY, NJ 1,747,6881.7m $96.5m $96.5m 0.16% Reduced -648.5k -648,546
11 PRICE T ROWE ASSOCIATES INC /MD/ 0.01% of their portfolio BALTIMORE, MD 1,630,6901.6m $90.0m $90.0m 0.01% Added +286.1k +286,137
12 RA CAPITAL MANAGEMENT, L.P. 1.17% of their portfolio BOSTON, MA 1,604,0141.6m $88.5m $88.5m 1.17% New
13 Cormorant Asset Management, LP 4.90% of their portfolio BOSTON, MA 1,525,0001.5m $84.2m $84.2m 4.90% Reduced -255.0k -255,000
14 MONTANOVA CAPITAL, LLC 3.42% of their portfolio New York, NY 1,516,2541.5m $83.7m $83.7m 3.42% Reduced -46.1k -46,100
15 T. Rowe Price Investment Management, Inc. 0.04% of their portfolio BALTIMORE, MD 1,173,7911.2m $64.8m $64.8m 0.04% Added +190.9k +190,929
16 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 935,186935.2k $51.6m $51.6m 0.00% Added +96.7k +96,717
17 Vestal Point Capital, LP 2.78% of their portfolio NEW YORK, NY 675,000675.0k $37.3m $37.3m 2.78% Added +575.0k +575,000
18 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 545,077545.1k $30.1m $30.1m 0.00% Reduced -1.5m -1,545,209
19 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 522,718522.7k $28.8m $28.8m 0.00% Reduced -580.8k -580,782
20 GREAT POINT PARTNERS LLC 5.20% of their portfolio Greenwich, CT 492,000492.0k $27.2m $27.2m 5.20% Added +192.0k +192,000
21 Affinity Asset Advisors, LLC 4.00% of their portfolio NEW YORK, NY 460,000460.0k $25.4m $25.4m 4.00% Added +160.0k +160,000
22 SAMSARA BIOCAPITAL, LLC 5.24% of their portfolio PALO ALTO, CA 453,641453.6k $25.0m $25.0m 5.24% Unchanged
23 DEUTSCHE BANK AG\ 0.01% of their portfolio FRANKFURT AM MAIN, 2M 446,530446.5k $24.6m $24.6m 0.01% Reduced -1.3k -1,253
24 NORTHERN TRUST CORP 0.00% of their portfolio CHICAGO, IL 350,580350.6k $19.3m $19.3m 0.00% Reduced -8.9k -8,880
25 BAMCO INC /NY/ 0.05% of their portfolio NEW YORK, NY 342,760342.8k $18.9m $18.9m 0.05% Added +93.8k +93,767
26 ADAGE CAPITAL PARTNERS GP, L.L.C. 0.03% of their portfolio Boston, MA 323,468323.5k $17.9m $17.9m 0.03% Added +51.5k +51,459
27 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio SAN FRANCISCO, CA 313,893313.9k $17.3m $17.3m 0.00% Added +31.9k +31,883
28 PFM Health Sciences, LP 0.94% of their portfolio SAN FRANCISCO, CA 311,980312.0k $17.2m $17.2m 0.94% Added +8.8k +8,770
29 UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio NEW YORK, NY 310,382310.4k $17.1m $17.1m 0.00% Added +45.0k +44,972
30 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 303,406303.4k $16.7m $16.7m 0.00% Reduced -111.1k -111,135
31 VICTORY CAPITAL MANAGEMENT INC 0.02% of their portfolio San Antonio, TX 283,872283.9k $15.7m $15.7m 0.02% Added +48.0k +48,006
32 STEMPOINT CAPITAL LP 4.56% of their portfolio NEW YORK, NY 280,709280.7k $15.5m $15.5m 4.56% Added +140.4k +140,442
33 Integral Health Asset Management, LLC 1.51% of their portfolio New York, NY 275,000275.0k $15.2m $15.2m 1.51% Added +20.0k +20,000
34 GOLDMAN SACHS GROUP INC 0.00% of their portfolio NEW YORK, NY 258,167258.2k $14.2m $14.2m 0.00% Reduced -14.6k -14,626
35 Russell Investments Group, Ltd. 0.02% of their portfolio Seattle, WA 235,591235.6k $13.0m $13.0m 0.02% Added +40.2k +40,154
36 VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.05% of their portfolio JUPITER, FL 234,728234.7k $13.0m $13.0m 0.05% Reduced -128.4k -128,365
37 VOYA INVESTMENT MANAGEMENT LLC 0.01% of their portfolio ATLANTA, GA 218,287218.3k $12.0m $12.0m 0.01% Reduced -164.3k -164,271
38 Candriam S.C.A. 0.07% of their portfolio STRASSEN, N4 217,008217.0k $12.0m $12.0m 0.07% Reduced -3.0k -3,000
39 EAGLE ASSET MANAGEMENT INC 0.05% of their portfolio ST PETERSBURG, FL 190,604190.6k $10.2m $10.2m 0.05% Reduced -33.9k -33,930
40 Cutter Capital Management, LP 3.15% of their portfolio NEW YORK, NY 187,000187.0k $10.3m $10.3m 3.15% Reduced -27.0k -27,000
41 Soleus Capital Management, L.P. 0.83% of their portfolio GREENWICH, CT 170,741170.7k $9.4m $9.4m 0.83% Added +20.7k +20,741
42 Parkman Healthcare Partners LLC 1.18% of their portfolio STAMFORD, CT 156,843156.8k $8.7m $8.7m 1.18% Added +245 +245
43 Bank of New York Mellon Corp 0.00% of their portfolio NEW YORK, NY 147,198147.2k $8.1m $8.1m 0.00% Added +26.1k +26,134
44 Qube Research & Technologies Ltd 0.01% of their portfolio LONDON, X0 144,636144.6k $8.0m $8.0m 0.01% Added +43.5k +43,450
45 TD Asset Management Inc 0.01% of their portfolio Toronto, A6 123,118123.1k $6.8m $6.8m 0.01% Added +33.2k +33,200
46 Nuveen Asset Management, LLC 0.00% of their portfolio CHICAGO, IL 121,911121.9k $6.7m $6.7m 0.00% Reduced -64.9k -64,872
47 Woodline Partners LP 0.06% of their portfolio San Francisco, CA 107,699107.7k $5.9m $5.9m 0.06% Added +3.6k +3,639
48 Man Group plc 0.02% of their portfolio LONDON, X0 104,046104.0k $5.7m $5.7m 0.02% New
49 Rafferty Asset Management, LLC 0.02% of their portfolio New York, NY 85,81285.8k $4.7m $4.7m 0.02% Reduced -40.9k -40,939
50 Duquesne Family Office LLC 0.15% of their portfolio New York, NY 74,10074.1k $4.1m $4.1m 0.15% Unchanged
51 MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio Toronto, A6 73,33273.3k $4.0m $4.0m 0.00% Added +26.1k +26,134
52 Thrivent Financial for Lutherans 0.01% of their portfolio Minneapolis, MN 64,02564.0k $3.5m $3.5m 0.01% Reduced -3.5k -3,515
53 UBS Group AG 0.00% of their portfolio ZURICH, V8 63,57763.6k $3.5m $3.5m 0.00% Reduced -39.9k -39,904
54 Swiss National Bank 0.00% of their portfolio ZURICH, V8 62,90062.9k $3.5m $3.5m 0.00% Added +6.5k +6,500
55 RHUMBLINE ADVISERS 0.00% of their portfolio BOSTON, MA 60,57060.6k $3.3m $3.3m 0.00% Added +7.6k +7,568
56 SUPERSTRING CAPITAL MANAGEMENT LP 4.11% of their portfolio NEW YORK, NY 59,13359.1k $3.3m $3.3m 4.11% New
57 FRANKLIN RESOURCES INC 0.00% of their portfolio San Mateo, CA 56,70156.7k $3.1m $3.1m 0.00% Added +2.4k +2,363
58 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 55,81155.8k $3.1m $3.1m 0.00% Added +16.2k +16,231
59 TWINBEECH CAPITAL LP 0.06% of their portfolio PURCHASE, NY 53,58553.6k $3.0m $3.0m 0.06% Added +23.1k +23,141
60 JANE STREET GROUP, LLC 0.00% of their portfolio NEW YORK, NY 52,01552.0k $2.9m $2.9m 0.00% Added +15.2k +15,158
61 HighVista Strategies LLC 1.03% of their portfolio BOSTON, MA 51,04051.0k $2.8m $2.8m 1.03% Reduced -21.2k -21,190
62 JACOBS LEVY EQUITY MANAGEMENT, INC 0.01% of their portfolio FLORHAM PARK, NJ 47,81747.8k $2.6m $2.6m 0.01% New
63 ACUTA CAPITAL PARTNERS, LLC 1.96% of their portfolio REDWOOD CITY, CA 42,20042.2k $2.3m $2.3m 1.96% Added +7.7k +7,700
64 MYDA Advisors LLC 0.71% of their portfolio WOODMERE, NY 42,00042.0k $2.3m $2.3m 0.71% Added +7.0k +7,000
65 ALPS ADVISORS INC 0.02% of their portfolio Denver, CO 41,72241.7k $2.3m $2.3m 0.02% Added +4.5k +4,487
66 Walleye Capital LLC 0.02% of their portfolio NEW YORK, NY 41,14441.1k $2.3m $2.3m 0.02% Reduced -53.1k -53,064
67 STATE OF WISCONSIN INVESTMENT BOARD 0.01% of their portfolio MADISON, WI 39,16539.2k $2.2m $2.2m 0.01% Added +12.5k +12,539
68 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio BALA CYNWYD, PA 39,15339.2k $2.2m $2.2m 0.00% Added +2.6k +2,578
69 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 37,47037.5k $2.1m $2.1m 0.00% Reduced -2.2k -2,233
70 PRINCIPAL FINANCIAL GROUP INC 0.00% of their portfolio DES MOINES, IA 37,35237.4k $2.1m $2.1m 0.00% Added +517 +517
71 WEXFORD CAPITAL LP 0.51% of their portfolio WEST PALM BEACH, FL 36,46436.5k $2.0m $2.0m 0.51% Added +30.6k +30,625
72 Legal & General Group Plc 0.00% of their portfolio London, X0 35,40535.4k $2.0m $2.0m 0.00% Added +6.1k +6,061
73 ALGERT GLOBAL LLC 0.06% of their portfolio SAN FRANCISCO, CA 35,21135.2k $1.9m $1.9m 0.06% Added +6.9k +6,901
74 TWO SIGMA INVESTMENTS, LP 0.00% of their portfolio NEW YORK, NY 34,46134.5k $1.9m $1.9m 0.00% Reduced -154.4k -154,393
75 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio WEST SACRAMENTO, CA 32,06432.1k $1.8m $1.8m 0.00% Added +2.5k +2,516
76 DekaBank Deutsche Girozentrale 0.00% of their portfolio FRANKFURT, 2M 30,00030.0k $2.1m $2.1m 0.00% Unchanged
77 Moody Aldrich Partners LLC 0.29% of their portfolio MARBLEHEAD, MA 27,33727.3k $1.5m $1.5m 0.29% Added +6.8k +6,777
78 RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio NEW YORK, NY 27,07227.1k $1.5m $1.5m 0.00% New
79 MetLife Investment Management, LLC 0.01% of their portfolio Whippany, NJ 24,98125.0k $1.4m $1.4m 0.01% Added +5.4k +5,387
80 Corebridge Financial, Inc. 0.01% of their portfolio HOUSTON, TX 23,18923.2k $1.3m $1.3m 0.01% First filing
81 Schonfeld Strategic Advisors LLC 0.01% of their portfolio NEW YORK, NY 23,14823.1k $1.3m $1.3m 0.01% Reduced -29.8k -29,776
82 CONGRESS ASSET MANAGEMENT CO 0.01% of their portfolio BOSTON, MA 22,98223.0k $1.3m $1.3m 0.01% Reduced -246 -246
83 MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd. 0.00% of their portfolio CAUSEWAY BAY, K3 22,75522.8k $1.3m $1.3m 0.00% First filing
84 Atle Fund Management AB 0.76% of their portfolio STOCKHOLM, V7 22,49622.5k $1.2m $1.2m 0.76% Added +5.0k +5,000
85 Connor, Clark & Lunn Investment Management Ltd. 0.01% of their portfolio VANCOUVER, A1 22,49222.5k $1.2m $1.2m 0.01% Reduced -23.2k -23,206
86 CITIGROUP INC 0.00% of their portfolio NEW YORK, NY 21,89221.9k $1.2m $1.2m 0.00% Reduced -93.1k -93,055
87 Invesco Ltd. 0.00% of their portfolio ATLANTA, GA 21,49821.5k $1.2m $1.2m 0.00% Added +1.3k +1,275
88 Erste Asset Management GmbH 0.02% of their portfolio VIENNA, C4 21,00021.0k $1.1m $1.1m 0.02% Unchanged
89 HARBOR CAPITAL ADVISORS, INC. 0.09% of their portfolio CHICAGO, IL 20,36220.4k $1.1m $1.1m 0.09% Added +1.6k +1,568
90 MARTINGALE ASSET MANAGEMENT L P 0.02% of their portfolio BOSTON, MA 20,19220.2k $1.1m $1.1m 0.02% Reduced -2.7k -2,740
91 WELLS FARGO & COMPANY/MN 0.00% of their portfolio SAN FRANCISCO, CA 19,99520.0k $1.1m $1.1m 0.00% Added +2.2k +2,161
92 NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio ALBANY, NY 18,89918.9k $1.0m $1.0m 0.00% Added +1.9k +1,924
93 WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio Boston, MA 18,20018.2k $1.0m $1.0m 0.00% Added +2.5k +2,503
94 FIRST TRUST ADVISORS LP 0.00% of their portfolio Wheaton, IL 16,89416.9k $932.4k $932.4k 0.00% Reduced -23.4k -23,383
95 AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio Greenwich, CT 16,85216.9k $930.1k $930.1k 0.00% Added +4.7k +4,718
96 Allianz Asset Management GmbH 0.00% of their portfolio MUNICH, 2M 16,80016.8k $927.2k $927.2k 0.00% Reduced -3.1k -3,100
97 PROFUND ADVISORS LLC 0.03% of their portfolio BETHESDA, MD 16,09616.1k $888.3k $888.3k 0.03% Reduced -3.9k -3,937
98 Allspring Global Investments Holdings, LLC 0.00% of their portfolio CHARLOTTE, NC 15,92815.9k $879.1k $879.1k 0.00% Added +4.4k +4,372
99 Y-Intercept (Hong Kong) Ltd 0.05% of their portfolio HONG KONG, K3 15,85915.9k $875.3k $875.3k 0.05% Added +6.4k +6,439
100 Squarepoint Ops LLC 0.00% of their portfolio NEW YORK, NY 15,82915.8k $873.6k $873.6k 0.00% Reduced -105.2k -105,182