Vault-13

ARCELLX INC ACLX

COMMON STOCK · Common Stock · CUSIP 03940C100

140 institutional holders +21 vs Q1 2023
49,335,05849.3m shares reported held*
$1.6bnreported value*
32 new 67 added 33 reduced 11 sold out net sold ≈ $664.5k (-21.0k 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 ($177.5k this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $31.62. Options: 5 managers hold calls ($1.0m notional), 5 hold puts ($1.7m).

Trends to Q2 2023

Institutional holders

Managers reporting a position, each quarter

050100150Q3 22: 74Q4 22: 127Q1 23: 119Q2 23: 140140Q3 22Q4 22Q1 23Q2 23
Numbers
QuarterHolders
Q3 202274
Q4 2022127
Q1 2023119
Q2 2023140

Buyers vs sellers

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

Bought or addedCut or sold out
1000100Q4 22: 86 bought or addedQ4 22: 32 cut or sold outQ4 22Q1 23: 61 bought or addedQ1 23: 63 cut or sold outQ1 23Q2 23: 99 bought or addedQ2 23: 44 cut or sold outQ2 23
Numbers
QuarterBought or addedCut or sold out
Q4 20228632
Q1 20236163
Q2 20239944

Calls vs puts

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

CallsPuts
$0$500k$1m$1.5m$2mQ3 22 calls: $681.0kQ3 22 puts: $187.0kQ3 22P/C 0.27Q4 22 calls: $1.5mQ4 22 puts: $331.1kQ4 22P/C 0.22Q1 23 calls: $1.1mQ1 23 puts: $1.2mQ1 23P/C 1.06Q2 23 calls: $1.0mQ2 23 puts: $1.7mQ2 23P/C 1.68
Numbers
QuarterCallsPutsP/C
Q3 2022$681.0k$187.0k0.27
Q4 2022$1.5m$331.1k0.22
Q1 2023$1.1m$1.2m1.06
Q2 2023$1.0m$1.7m1.68

Biggest buyers

PRICE T ROWE ASSOCIATES INC /MD/ Added +1,035,556+1.0m
Paradigm Biocapital Advisors LP Added +589,221+589.2k
VANGUARD GROUP INC Added +567,631+567.6k
Logos Global Management LP New +500,000+500.0k
MONTANOVA CAPITAL, LLC Added +449,846+449.8k
Cormorant Asset Management, LP Added +400,000+400.0k
LORD, ABBETT & CO. LLC Added +386,330+386.3k
BlackRock Inc. Added +380,128+380.1k
RENAISSANCE TECHNOLOGIES LLC Added +328,167+328.2k
TWO SIGMA INVESTMENTS, LP Added +186,467+186.5k

Biggest sellers

SR One Capital Management, LP Reduced -1,553,377-1.6m
CITADEL ADVISORS LLC Reduced -1,153,821-1.2m
NEA Management Company, LLC Reduced -1,000,000-1.0m
FMR LLC Reduced -675,182-675.2k
PICTET ASSET MANAGEMENT SA Reduced -471,802-471.8k
BRAIDWELL LP Sold out -333,800-333.8k
SAMSARA BIOCAPITAL, LLC Reduced -295,658-295.7k
PFM Health Sciences, LP Reduced -269,984-270.0k
GOLDMAN SACHS GROUP INC Reduced -251,812-251.8k
Soleus Capital Management, L.P. Reduced -246,148-246.1k

Biggest calls

SUSQUEHANNA INTERNATIONAL GROUP, LLP New $743.1k23.5k shares
CITADEL ADVISORS LLC Added $215.0k6.8k shares
GROUP ONE TRADING LLC Added $53.8k1.7k shares
SIMPLEX TRADING, LLC Reduced $3.0k100 shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 shares

Biggest puts

JANE STREET GROUP, LLC New $1.6m49.9k shares
CITADEL ADVISORS LLC Reduced $123.3k3.9k shares
GROUP ONE TRADING LLC New $3.2k100 shares
SIMPLEX TRADING, LLC Reduced $3.0k100 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 2023

#ManagerLocationShares Value% of their portfolioChangeShares change
1 FMR LLC 0.01% of their portfolio BOSTON, MA 4,690,9984.7m $148.3m $148.3m 0.01% Reduced -675.2k -675,182
2 PERCEPTIVE ADVISORS LLC 3.69% of their portfolio NEW YORK, NY 4,016,3974.0m $127.0m $127.0m 3.69% Added +174.7k +174,658
3 SR One Capital Management, LP 53.81% of their portfolio Redwood City, CA 3,946,6303.9m $124.8m $124.8m 53.81% Reduced -1.6m -1,553,377
4 NEA Management Company, LLC 9.04% of their portfolio TIMONIUM, MD 3,745,2623.7m $118.4m $118.4m 9.04% Reduced -1.0m -1,000,000
5 MONTANOVA CAPITAL, LLC 4.82% of their portfolio New York, NY 2,848,1672.8m $90.1m $90.1m 4.82% Added +449.8k +449,846
6 BlackRock Inc. 0.00% of their portfolio New York, NY 2,602,4852.6m $82.3m $82.3m 0.00% Added +380.1k +380,128
7 LORD, ABBETT & CO. LLC 0.14% of their portfolio JERSEY CITY, NJ 2,530,7442.5m $80.0m $80.0m 0.14% Added +386.3k +386,330
8 Paradigm Biocapital Advisors LP 6.01% of their portfolio NEW YORK, NY 2,347,0002.3m $74.2m $74.2m 6.01% Added +589.2k +589,221
9 Cormorant Asset Management, LP 3.60% of their portfolio BOSTON, MA 2,000,0002.0m $63.2m $63.2m 3.60% Added +400.0k +400,000
10 VANGUARD GROUP INC 0.00% of their portfolio Valley Forge, PA 1,994,5872.0m $63.1m $63.1m 0.00% Added +567.6k +567,631
11 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 1,931,7651.9m $61.1m $61.1m 0.00% Added +57.3k +57,309
12 JANUS HENDERSON GROUP PLC 0.03% of their portfolio LONDON, X0 1,754,2471.8m $55.5m $55.5m 0.03% Added +167.0k +166,995
13 PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio BALTIMORE, MD 1,057,7811.1m $33.4m $33.4m 0.00% Added +1.0m +1,035,556
14 GOLDMAN SACHS GROUP INC 0.01% of their portfolio NEW YORK, NY 1,018,9141.0m $32.2m $32.2m 0.01% Reduced -251.8k -251,812
15 Soleus Capital Management, L.P. 3.52% of their portfolio GREENWICH, CT 1,001,9991.0m $31.7m $31.7m 3.52% Reduced -246.1k -246,148
16 NOVO HOLDINGS A/S 2.44% of their portfolio HELLERUP, G7 1,000,0001.0m $31.6m $31.6m 2.44% Reduced -225.0k -225,000
17 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 685,228685.2k $21.7m $21.7m 0.00% Added +123.6k +123,624
18 SAMSARA BIOCAPITAL, LLC 3.41% of their portfolio PALO ALTO, CA 613,921613.9k $19.4m $19.4m 3.41% Reduced -295.7k -295,658
19 PICTET ASSET MANAGEMENT SA 0.02% of their portfolio GENEVA 73, V8 556,408556.4k $17.6m $17.6m 0.02% Reduced -471.8k -471,802
20 Logos Global Management LP 2.18% of their portfolio San Francisco, CA 500,000500.0k $15.8m $15.8m 2.18% New
21 Vivo Capital, LLC 0.95% of their portfolio Palo Alto, CA 433,785433.8k $13.7m $13.7m 0.95% Added +143.1k +143,072
22 Candriam S.C.A. 0.09% of their portfolio STRASSEN, N4 398,020398.0k $12.6m $12.6m 0.09% Reduced -49.1k -49,134
23 ADAGE CAPITAL PARTNERS GP, L.L.C. 0.03% of their portfolio Boston, MA 372,904372.9k $11.8m $11.8m 0.03% Reduced -4.0k -4,000
24 CITADEL ADVISORS LLC 0.01% of their portfolio MIAMI, FL 361,075361.1k $11.4m $11.4m 0.01% Reduced -1.2m -1,153,821
25 NORTHERN TRUST CORP 0.00% of their portfolio CHICAGO, IL 359,550359.6k $11.4m $11.4m 0.00% Added +93.4k +93,386
26 RENAISSANCE TECHNOLOGIES LLC 0.02% of their portfolio NEW YORK, NY 344,667344.7k $10.9m $10.9m 0.02% Added +328.2k +328,167
27 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 327,438327.4k $10.4m $10.4m 0.00% Reduced -221.8k -221,759
28 TWO SIGMA INVESTMENTS, LP 0.03% of their portfolio NEW YORK, NY 326,093326.1k $10.3m $10.3m 0.03% Added +186.5k +186,467
29 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 279,111279.1k $8.8m $8.8m 0.00% Added +170.7k +170,713
30 VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.04% of their portfolio JUPITER, FL 274,571274.6k $8.7m $8.7m 0.04% Added +119.4k +119,418
31 PFM Health Sciences, LP 0.33% of their portfolio SAN FRANCISCO, CA 255,832255.8k $8.1m $8.1m 0.33% Reduced -270.0k -269,984
32 MILLENNIUM MANAGEMENT LLC 0.01% of their portfolio NEW YORK, NY 242,135242.1k $7.7m $7.7m 0.01% Added +121.3k +121,337
33 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio SAN FRANCISCO, CA 240,938240.9k $7.6m $7.6m 0.00% Added +33.7k +33,687
34 Nuveen Asset Management, LLC 0.00% of their portfolio CHICAGO, IL 237,066237.1k $7.5m $7.5m 0.00% Added +138.6k +138,577
35 Affinity Asset Advisors, LLC 2.82% of their portfolio NEW YORK, NY 226,275226.3k $7.2m $7.2m 2.82% Added +23.4k +23,441
36 Walleye Capital LLC 0.12% of their portfolio NEW YORK, NY 217,634217.6k $6.9m $6.9m 0.12% Added +57.2k +57,191
37 Parkman Healthcare Partners LLC 1.07% of their portfolio STAMFORD, CT 195,260195.3k $6.2m $6.2m 1.07% Added +47.6k +47,614
38 FEDERATED HERMES, INC. 0.01% of their portfolio PITTSBURGH, PA 164,671164.7k $5.2m $5.2m 0.01% Added +153.9k +153,922
39 DEUTSCHE BANK AG\ 0.00% of their portfolio FRANKFURT AM MAIN, 2M 146,011146.0k $4.6m $4.6m 0.00% Added +127.7k +127,694
40 Rafferty Asset Management, LLC 0.03% of their portfolio New York, NY 144,096144.1k $4.6m $4.6m 0.03% Added +2.7k +2,679
41 Bank of New York Mellon Corp 0.00% of their portfolio NEW YORK, NY 130,524130.5k $4.1m $4.1m 0.00% Added +5.5k +5,503
42 TWO SIGMA ADVISERS, LP 0.01% of their portfolio NEW YORK, NY 129,800129.8k $4.1m $4.1m 0.01% Added +76.2k +76,200
43 UBS Group AG 0.00% of their portfolio ZURICH, V8 121,507121.5k $3.8m $3.8m 0.00% Added +120.5k +120,515
44 Russell Investments Group, Ltd. 0.01% of their portfolio Seattle, WA 116,342116.3k $3.7m $3.7m 0.01% Added +66.2k +66,210
45 Qube Research & Technologies Ltd 0.01% of their portfolio LONDON, X0 110,744110.7k $3.5m $3.5m 0.01% New
46 Cubist Systematic Strategies, LLC 0.04% of their portfolio STAMFORD, CT 108,589108.6k $3.4m $3.4m 0.04% Added +80.8k +80,800
47 CLOUGH CAPITAL PARTNERS L P 0.34% of their portfolio Boston, MA 105,862105.9k $3.3m $3.3m 0.34% Reduced -91.6k -91,616
48 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 90,70590.7k $2.9m $2.9m 0.00% Reduced -97.5k -97,550
49 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio WEST SACRAMENTO, CA 86,01386.0k $2.7m $2.7m 0.00% Added +61.5k +61,534
50 SPHERA FUNDS MANAGEMENT LTD. 0.53% of their portfolio TEL AVIV, L3 77,48877.5k $2.5m $2.5m 0.53% Reduced -90.0k -90,000
51 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 75,59675.6k $2.4m $2.4m 0.00% Added +16.5k +16,482
52 JANE STREET GROUP, LLC 0.00% of their portfolio NEW YORK, NY 73,93073.9k $2.3m $2.3m 0.00% Added +57.7k +57,739
53 CITIGROUP INC 0.00% of their portfolio NEW YORK, NY 63,39863.4k $2.0m $2.0m 0.00% Reduced -50.2k -50,205
54 HighVista Strategies LLC 0.91% of their portfolio BOSTON, MA 62,86962.9k $2.0m $2.0m 0.91% Added +8.6k +8,589
55 VOYA INVESTMENT MANAGEMENT LLC 0.00% of their portfolio ATLANTA, GA 56,98357.0k $1.8m $1.8m 0.00% Reduced -29.2k -29,153
56 WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio Boston, MA 56,20256.2k $1.8m $1.8m 0.00% Reduced -56.3k -56,261
57 SCHRODER INVESTMENT MANAGEMENT GROUP 0.00% of their portfolio London, X0 55,97756.0k $1.8m $1.8m 0.00% New
58 Informed Momentum Co LLC 0.33% of their portfolio SOLANA BEACH, CA 55,71455.7k $1.8m $1.8m 0.33% Reduced -48.6k -48,587
59 Swiss National Bank 0.00% of their portfolio ZURICH, V8 52,10052.1k $1.6m $1.6m 0.00% Added +19.0k +19,000
60 RHUMBLINE ADVISERS 0.00% of their portfolio BOSTON, MA 50,42950.4k $1.6m $1.6m 0.00% Added +3.9k +3,915
61 Schonfeld Strategic Advisors LLC 0.01% of their portfolio NEW YORK, NY 49,25849.3k $1.6m $1.6m 0.01% Added +13.7k +13,662
62 MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio Toronto, A6 42,86842.9k $1.4m $1.4m 0.00% Added +30.7k +30,712
63 AQR CAPITAL MANAGEMENT LLC 0.00% of their portfolio Greenwich, CT 42,26042.3k $1.3m $1.3m 0.00% New
64 VICTORY CAPITAL MANAGEMENT INC 0.00% of their portfolio San Antonio, TX 41,70541.7k $1.3m $1.3m 0.00% New
65 PUTNAM INVESTMENTS LLC 0.00% of their portfolio BOSTON, MA 41,61241.6k $1.3m $1.3m 0.00% Reduced -12.1k -12,057
66 WELLS FARGO & COMPANY/MN 0.00% of their portfolio SAN FRANCISCO, CA 40,52640.5k $1.3m $1.3m 0.00% Added +7.7k +7,730
67 FIRST TRUST ADVISORS LP 0.00% of their portfolio Wheaton, IL 40,30140.3k $1.3m $1.3m 0.00% Added +22.2k +22,225
68 BAMCO INC /NY/ 0.00% of their portfolio NEW YORK, NY 40,00040.0k $1.3m $1.3m 0.00% New
69 Knott David M Jr 0.51% of their portfolio SYOSSET, NY 40,00040.0k $1.3m $1.3m 0.51% Added +12.0k +12,000
70 Squarepoint Ops LLC 0.01% of their portfolio NEW YORK, NY 39,29539.3k $1.2m $1.2m 0.01% Added +22.6k +22,554
71 GREAT POINT PARTNERS LLC 0.24% of their portfolio Greenwich, CT 37,50037.5k $1.2m $1.2m 0.24% Reduced -219.5k -219,506
72 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 36,21036.2k $1.1m $1.1m 0.00% Added +9.5k +9,510
73 ALPS ADVISORS INC 0.01% of their portfolio Denver, CO 35,27835.3k $1.1m $1.1m 0.01% Added +6.4k +6,387
74 CREDIT SUISSE AG/ 0.00% of their portfolio ZURICH, V8 34,95335.0k $1.1m $1.1m 0.00% Added +22.1k +22,059
75 TWINBEECH CAPITAL LP 0.02% of their portfolio PURCHASE, NY 32,66832.7k $1.0m $1.0m 0.02% New
76 TD Asset Management Inc 0.00% of their portfolio Toronto, A6 28,80028.8k $910.7k $910.7k 0.00% New
77 Jump Financial, LLC 0.03% of their portfolio Chicago, IL 26,79626.8k $847.3k $847.3k 0.03% Reduced -3.4k -3,355
78 PROFUND ADVISORS LLC 0.04% of their portfolio BETHESDA, MD 26,34526.3k $833.0k $833.0k 0.04% Added +56 +56
79 Jefferies Financial Group Inc. 0.02% of their portfolio NEW YORK, NY 25,47625.5k $805.6k $805.6k 0.02% New
80 CONGRESS ASSET MANAGEMENT CO 0.01% of their portfolio BOSTON, MA 25,04525.0k $791.9k $791.9k 0.01% New
81 STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio MADISON, WI 24,71824.7k $781.6k $781.6k 0.00% Added +11.0k +10,955
82 Legal & General Group Plc 0.00% of their portfolio London, X0 24,63724.6k $779.0k $779.0k 0.00% Added +17.5k +17,484
83 Mirae Asset Global Investments Co., Ltd. 0.00% of their portfolio SEOUL, M5 23,35323.4k $736.2k $736.2k 0.00% Added +3.7k +3,679
84 ADAMS STREET PARTNERS LLC 0.19% of their portfolio CHICAGO, IL 22,92422.9k $724.9k $724.9k 0.19% New
85 Aigen Investment Management, LP 0.10% of their portfolio NEW YORK, NY 20,56420.6k $650.2k $650.2k 0.10% New
86 MARTINGALE ASSET MANAGEMENT L P 0.01% of their portfolio BOSTON, MA 20,22820.2k $639.6k $639.6k 0.01% New
87 D. E. Shaw & Co., Inc. 0.00% of their portfolio New York, NY 20,21020.2k $639.0k $639.0k 0.00% New
88 MetLife Investment Management, LLC 0.00% of their portfolio Whippany, NJ 20,18420.2k $638.2k $638.2k 0.00% Added +3.3k +3,338
89 TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY 0.01% of their portfolio FRANKFORT, KY 18,44318.4k $583.0k $583.0k 0.01% Reduced -1.5k -1,528
90 AMERICAN INTERNATIONAL GROUP, INC. 0.00% of their portfolio New York, NY 18,26818.3k $577.6k $577.6k 0.00% Added +4.0k +3,996
91 Invesco Ltd. 0.00% of their portfolio ATLANTA, GA 17,76817.8k $561.8k $561.8k 0.00% Added +3.9k +3,927
92 UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC 0.00% of their portfolio NEW YORK, NY 16,60016.6k $511.4k $511.4k 0.00% Unchanged
93 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio BALA CYNWYD, PA 16,10216.1k $509.1k $509.1k 0.00% Reduced -41.4k -41,355
94 DekaBank Deutsche Girozentrale 0.00% of their portfolio FRANKFURT, 2M 16,00016.0k $499.0k $499.0k 0.00% Unchanged
95 NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio ALBANY, NY 15,32615.3k $484.6k $484.6k 0.00% Added +271 +271
96 Walleye Trading LLC 0.02% of their portfolio NEW YORK, NY 14,42514.4k $456.1k $456.1k 0.02% Added +5.4k +5,433
97 Utah Retirement Systems 0.01% of their portfolio SALT LAKE CITY, UT 12,89512.9k $407.7k $407.7k 0.01% New
98 Graham Capital Management, L.P. 0.01% of their portfolio ROWAYTON, CT 12,51412.5k $395.7k $395.7k 0.01% New
99 HighTower Advisors, LLC 0.00% of their portfolio CHICAGO, IL 12,29012.3k $388.0k $388.0k 0.00% Added +64 +64
100 GLOBEFLEX CAPITAL L P 0.04% of their portfolio SAN DIEGO, CA 12,20012.2k $385.8k $385.8k 0.04% New