Vault-13

ARCELLX INC ACLX

COMMON STOCK · Common Stock · CUSIP 03940C100

119 institutional holders -8 vs Q4 2022
49,338,79749.3m shares reported held*
$1.5bnreported value*
15 new 46 added 43 reduced 20 sold out net bought ≈ $218.7m (+7.1m 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 ($705.2k this quarter). Holder counts are more reliable. Implied quarter-end price ≈ $30.79. Options: 5 managers hold calls ($1.1m notional), 4 hold puts ($1.2m).

Trends to Q1 2023

Institutional holders

Managers reporting a position, each quarter

050100150Q3 22: 74Q4 22: 127Q1 23: 119119Q3 22Q4 22Q1 23
Numbers
QuarterHolders
Q3 202274
Q4 2022127
Q1 2023119

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 23
Numbers
QuarterBought or addedCut or sold out
Q4 20228632
Q1 20236163

Calls vs puts

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

CallsPuts
$0$500k$1m$1.5mQ3 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 1.06
Numbers
QuarterCallsPutsP/C
Q3 2022$681.0k$187.0k0.27
Q4 2022$1.5m$331.1k0.22
Q1 2023$1.1m$1.2m1.06

Biggest buyers

FMR LLC Added +4,072,580+4.1m
PERCEPTIVE ADVISORS LLC Added +1,243,434+1.2m
GOLDMAN SACHS GROUP INC Added +1,148,609+1.1m
LORD, ABBETT & CO. LLC Added +1,047,420+1.0m
Paradigm Biocapital Advisors LP Added +875,678+875.7k
BRAIDWELL LP New +333,800+333.8k
Vivo Capital, LLC New +290,713+290.7k
STATE STREET CORP Added +258,365+258.4k
GREAT POINT PARTNERS LLC New +257,006+257.0k
Soleus Capital Management, L.P. Added +145,700+145.7k

Biggest sellers

Commodore Capital LP Sold out -591,437-591.4k
Cormorant Asset Management, LP Reduced -475,000-475.0k
NOVO HOLDINGS A/S Reduced -259,020-259.0k
Balyasny Asset Management L.P. Sold out -250,477-250.5k
TimesSquare Capital Management, LLC Sold out -218,910-218.9k
JPMORGAN CHASE & CO Reduced -194,801-194.8k
PATHWAY CAPITAL MANAGEMENT, LP Sold out -189,120-189.1k
CITADEL ADVISORS LLC Reduced -180,910-180.9k
CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM Reduced -140,325-140.3k
TEACHER RETIREMENT SYSTEM OF TEXAS Sold out -112,107-112.1k

Biggest calls

SIMPLEX TRADING, LLC Added $600.0k19.5k shares
Caption Management, LLC New $385.1k12.5k shares
CITADEL ADVISORS LLC Reduced $126.3k4.1k shares
GROUP ONE TRADING LLC New $9.2k300 shares
CONCOURSE FINANCIAL GROUP SECURITIES, INC. Unchanged $00 shares

Biggest puts

CITADEL ADVISORS LLC Added $403.6k13.1k shares
SIMPLEX TRADING, LLC Added $397.0k12.9k shares
Caption Management, LLC New $385.1k12.5k 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, Q1 2023

#ManagerLocationShares Value% of their portfolioChangeShares change
1 SR One Capital Management, LP 63.12% of their portfolio Redwood City, CA 5,500,0075.5m $169.5m $169.5m 63.12% Unchanged
2 FMR LLC 0.01% of their portfolio BOSTON, MA 5,366,1805.4m $165.3m $165.3m 0.01% Added +4.1m +4,072,580
3 NEA Management Company, LLC 10.11% of their portfolio TIMONIUM, MD 4,745,2624.7m $146.2m $146.2m 10.11% Unchanged
4 PERCEPTIVE ADVISORS LLC 3.50% of their portfolio NEW YORK, NY 3,841,7393.8m $118.4m $118.4m 3.50% Added +1.2m +1,243,434
5 MONTANOVA CAPITAL, LLC 3.57% of their portfolio New York, NY 2,398,3212.4m $73.9m $73.9m 3.57% Added +48.0k +47,988
6 BlackRock Inc. 0.00% of their portfolio New York, NY 2,222,3572.2m $68.5m $68.5m 0.00% Added +15.2k +15,178
7 LORD, ABBETT & CO. LLC 0.12% of their portfolio JERSEY CITY, NJ 2,144,4142.1m $66.1m $66.1m 0.12% Added +1.0m +1,047,420
8 STATE STREET CORP 0.00% of their portfolio BOSTON, MA 1,874,4561.9m $57.8m $57.8m 0.00% Added +258.4k +258,365
9 Paradigm Biocapital Advisors LP 5.13% of their portfolio NEW YORK, NY 1,757,7791.8m $54.2m $54.2m 5.13% Added +875.7k +875,678
10 Cormorant Asset Management, LP 3.25% of their portfolio BOSTON, MA 1,600,0001.6m $49.3m $49.3m 3.25% Reduced -475.0k -475,000
11 JANUS HENDERSON GROUP PLC 0.03% of their portfolio LONDON, X0 1,587,2521.6m $48.9m $48.9m 0.03% Reduced -84.9k -84,895
12 CITADEL ADVISORS LLC 0.05% of their portfolio MIAMI, FL 1,514,8961.5m $46.7m $46.7m 0.05% Reduced -180.9k -180,910
13 VANGUARD GROUP INC 0.00% of their portfolio Valley Forge, PA 1,426,9561.4m $44.0m $44.0m 0.00% Reduced -59.9k -59,898
14 GOLDMAN SACHS GROUP INC 0.01% of their portfolio NEW YORK, NY 1,270,7261.3m $39.2m $39.2m 0.01% Added +1.1m +1,148,609
15 Soleus Capital Management, L.P. 4.76% of their portfolio GREENWICH, CT 1,248,1471.2m $38.5m $38.5m 4.76% Added +145.7k +145,700
16 NOVO HOLDINGS A/S 2.49% of their portfolio HELLERUP, G7 1,225,0001.2m $37.7m $37.7m 2.49% Reduced -259.0k -259,020
17 PICTET ASSET MANAGEMENT SA 0.04% of their portfolio GENEVA 73, V8 1,028,2101.0m $31.7m $31.7m 0.04% Added +133.0k +133,001
18 SAMSARA BIOCAPITAL, LLC 5.79% of their portfolio PALO ALTO, CA 909,579909.6k $28.0m $28.0m 5.79% Reduced -47.9k -47,872
19 GEODE CAPITAL MANAGEMENT, LLC 0.00% of their portfolio BOSTON, MA 561,604561.6k $17.3m $17.3m 0.00% Added +16.8k +16,834
20 JPMORGAN CHASE & CO 0.00% of their portfolio NEW YORK, NY 549,197549.2k $16.9m $16.9m 0.00% Reduced -194.8k -194,801
21 PFM Health Sciences, LP 0.75% of their portfolio SAN FRANCISCO, CA 525,816525.8k $16.2m $16.2m 0.75% Reduced -90.7k -90,699
22 Candriam S.C.A. 0.09% of their portfolio STRASSEN, N4 447,154447.2k $12.7m $12.7m 0.09% Added +25.0k +25,000
23 ADAGE CAPITAL PARTNERS GP, L.L.C. 0.03% of their portfolio Boston, MA 376,904376.9k $11.6m $11.6m 0.03% Reduced -50.0k -50,000
24 BRAIDWELL LP 0.34% of their portfolio STAMFORD, CT 333,800333.8k $10.3m $10.3m 0.34% New
25 Vivo Capital, LLC 0.62% of their portfolio Palo Alto, CA 290,713290.7k $9.0m $9.0m 0.62% New
26 NORTHERN TRUST CORP 0.00% of their portfolio CHICAGO, IL 266,164266.2k $8.2m $8.2m 0.00% Reduced -10.8k -10,814
27 GREAT POINT PARTNERS LLC 1.56% of their portfolio Greenwich, CT 257,006257.0k $7.9m $7.9m 1.56% New
28 CHARLES SCHWAB INVESTMENT MANAGEMENT INC 0.00% of their portfolio SAN FRANCISCO, CA 207,251207.3k $6.4m $6.4m 0.00% Reduced -423 -423
29 Affinity Asset Advisors, LLC 2.40% of their portfolio NEW YORK, NY 202,834202.8k $6.2m $6.2m 2.40% Reduced -37.3k -37,309
30 CLOUGH CAPITAL PARTNERS L P 0.66% of their portfolio Boston, MA 197,478197.5k $6.1m $6.1m 0.66% Reduced -39.5k -39,500
31 BANK OF AMERICA CORP /DE/ 0.00% of their portfolio CHARLOTTE, NC 188,255188.3k $5.8m $5.8m 0.00% Added +107.9k +107,888
32 SPHERA FUNDS MANAGEMENT LTD. 1.12% of their portfolio TEL AVIV, L3 167,488167.5k $5.2m $5.2m 1.12% Reduced -70.0k -70,000
33 Walleye Capital LLC 0.10% of their portfolio NEW YORK, NY 160,443160.4k $4.9m $4.9m 0.10% Added +144.2k +144,173
34 VOLORIDGE INVESTMENT MANAGEMENT, LLC 0.02% of their portfolio JUPITER, FL 155,153155.2k $4.8m $4.8m 0.02% Added +54.5k +54,475
35 Altium Capital Management LLC 2.76% of their portfolio NEW YORK, NY 150,000150.0k $4.6m $4.6m 2.76% Unchanged
36 Parkman Healthcare Partners LLC 0.99% of their portfolio STAMFORD, CT 147,646147.6k $4.5m $4.5m 0.99% Added +26.6k +26,553
37 Rafferty Asset Management, LLC 0.03% of their portfolio New York, NY 141,417141.4k $4.4m $4.4m 0.03% Added +31.2k +31,199
38 TWO SIGMA INVESTMENTS, LP 0.01% of their portfolio NEW YORK, NY 139,626139.6k $4.3m $4.3m 0.01% Reduced -15.4k -15,380
39 Bank of New York Mellon Corp 0.00% of their portfolio NEW YORK, NY 125,021125.0k $3.9m $3.9m 0.00% Reduced -6.1k -6,144
40 CAAS CAPITAL MANAGEMENT LP 1.25% of their portfolio NEW YORK, NY 124,959125.0k $3.8m $3.8m 1.25% Reduced -5.0k -5,000
41 MILLENNIUM MANAGEMENT LLC 0.00% of their portfolio NEW YORK, NY 120,798120.8k $3.7m $3.7m 0.00% Added +50.5k +50,521
42 CITIGROUP INC 0.00% of their portfolio NEW YORK, NY 113,603113.6k $3.5m $3.5m 0.00% Added +64.3k +64,275
43 WELLINGTON MANAGEMENT GROUP LLP 0.00% of their portfolio Boston, MA 112,463112.5k $3.5m $3.5m 0.00% Added +43.8k +43,794
44 MORGAN STANLEY 0.00% of their portfolio NEW YORK, NY 108,398108.4k $3.3m $3.3m 0.00% Reduced -15.1k -15,097
45 Informed Momentum Co LLC 0.63% of their portfolio SOLANA BEACH, CA 104,301104.3k $3.2m $3.2m 0.63% Reduced -24.2k -24,224
46 Nuveen Asset Management, LLC 0.00% of their portfolio CHICAGO, IL 98,48998.5k $3.0m $3.0m 0.00% Added +8.7k +8,686
47 VOYA INVESTMENT MANAGEMENT LLC 0.00% of their portfolio ATLANTA, GA 86,13686.1k $2.7m $2.7m 0.00% Reduced -26.7k -26,705
48 BARCLAYS PLC 0.00% of their portfolio LONDON, X0 59,11459.1k $1.8m $1.8m 0.00% Reduced -10.2k -10,208
49 SUSQUEHANNA INTERNATIONAL GROUP, LLP 0.00% of their portfolio BALA CYNWYD, PA 57,45757.5k $1.8m $1.8m 0.00% Added +45.7k +45,694
50 HighVista Strategies LLC 1.36% of their portfolio BOSTON, MA 54,28054.3k $1.7m $1.7m 1.36% New
51 PUTNAM INVESTMENTS LLC 0.00% of their portfolio BOSTON, MA 53,66953.7k $1.7m $1.7m 0.00% Added +34.3k +34,266
52 TWO SIGMA ADVISERS, LP 0.00% of their portfolio NEW YORK, NY 53,60053.6k $1.7m $1.7m 0.00% Added +22.3k +22,300
53 Russell Investments Group, Ltd. 0.00% of their portfolio Seattle, WA 50,13250.1k $1.5m $1.5m 0.00% Added +25.6k +25,589
54 RHUMBLINE ADVISERS 0.00% of their portfolio BOSTON, MA 46,51446.5k $1.4m $1.4m 0.00% Added +3.5k +3,525
55 Schonfeld Strategic Advisors LLC 0.01% of their portfolio NEW YORK, NY 35,59635.6k $1.1m $1.1m 0.01% Added +21.3k +21,294
56 Swiss National Bank 0.00% of their portfolio ZURICH, V8 33,10033.1k $1.0m $1.0m 0.00% Reduced -3.9k -3,900
57 WELLS FARGO & COMPANY/MN 0.00% of their portfolio SAN FRANCISCO, CA 32,79632.8k $1.0m $1.0m 0.00% Added +30.1k +30,136
58 Kynam Capital Management, LP 0.12% of their portfolio PRINCETON, NJ 31,33631.3k $965.5k $965.5k 0.12% New
59 Jump Financial, LLC 0.04% of their portfolio Chicago, IL 30,15130.2k $929.0k $929.0k 0.04% Reduced -2.9k -2,851
60 ALPS ADVISORS INC 0.01% of their portfolio Denver, CO 28,89128.9k $890.1k $890.1k 0.01% Reduced -835 -835
61 Knott David M Jr 0.35% of their portfolio SYOSSET, NY 28,00028.0k $863.0k $863.0k 0.35% New
62 Cubist Systematic Strategies, LLC 0.01% of their portfolio STAMFORD, CT 27,78927.8k $856.2k $856.2k 0.01% Reduced -45.3k -45,343
63 ALLIANCEBERNSTEIN L.P. 0.00% of their portfolio NASHVILLE, TN 26,70026.7k $822.6k $822.6k 0.00% Unchanged
64 PROFUND ADVISORS LLC 0.05% of their portfolio BETHESDA, MD 26,28926.3k $810.0k $810.0k 0.05% New
65 CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM 0.00% of their portfolio WEST SACRAMENTO, CA 24,47924.5k $754.2k $754.2k 0.00% Reduced -140.3k -140,325
66 Vident Investment Advisory, LLC 0.02% of their portfolio Alpharetta, GA 22,75522.8k $701.1k $701.1k 0.02% Reduced -785 -785
67 PRICE T ROWE ASSOCIATES INC /MD/ 0.00% of their portfolio BALTIMORE, MD 22,22522.2k $686.0k $686.0k 0.00% Reduced -71.2k -71,244
68 Allianz Asset Management GmbH 0.00% of their portfolio MUNICH, 2M 21,30021.3k $656.3k $656.3k 0.00% Unchanged
69 TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY 0.01% of their portfolio FRANKFORT, KY 19,97120.0k $615.0k $615.0k 0.01% Unchanged
70 SEI INVESTMENTS CO 0.00% of their portfolio OAKS, PA 19,94519.9k $614.5k $614.5k 0.00% Reduced -5.2k -5,173
71 Mirae Asset Global Investments Co., Ltd. 0.00% of their portfolio SEOUL, M5 19,67419.7k $606.2k $606.2k 0.00% Added +5.3k +5,332
72 ALGERT GLOBAL LLC 0.03% of their portfolio SAN FRANCISCO, CA 19,62219.6k $604.6k $604.6k 0.03% Added +12.0k +12,022
73 STRS OHIO 0.00% of their portfolio COLUMBUS, OH 18,60018.6k $573.0k $573.0k 0.00% Reduced -34.2k -34,164
74 DEUTSCHE BANK AG\ 0.00% of their portfolio FRANKFURT AM MAIN, 2M 18,31718.3k $564.3k $564.3k 0.00% Added +5.7k +5,732
75 FIRST TRUST ADVISORS LP 0.00% of their portfolio Wheaton, IL 18,07618.1k $556.9k $556.9k 0.00% Reduced -12.0k -12,011
76 MetLife Investment Management, LLC 0.00% of their portfolio Whippany, NJ 16,84616.8k $519.0k $519.0k 0.00% Reduced -21.5k -21,490
77 Squarepoint Ops LLC 0.00% of their portfolio NEW YORK, NY 16,74116.7k $515.8k $515.8k 0.00% Reduced -8.5k -8,529
78 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% Added +2.9k +2,900
79 RENAISSANCE TECHNOLOGIES LLC 0.00% of their portfolio NEW YORK, NY 16,50016.5k $508.0k $508.0k 0.00% Reduced -34.3k -34,300
80 JANE STREET GROUP, LLC 0.00% of their portfolio NEW YORK, NY 16,19116.2k $498.8k $498.8k 0.00% New
81 DekaBank Deutsche Girozentrale 0.00% of their portfolio FRANKFURT, 2M 16,00016.0k $488.0k $488.0k 0.00% Unchanged
82 NEW YORK STATE COMMON RETIREMENT FUND 0.00% of their portfolio ALBANY, NY 15,05515.1k $463.8k $463.8k 0.00% Reduced -7.0k -6,991
83 FRED ALGER MANAGEMENT, LLC 0.00% of their portfolio NEW YORK, NY 14,37414.4k $442.9k $442.9k 0.00% Reduced -4.1k -4,059
84 AMERICAN INTERNATIONAL GROUP, INC. 0.00% of their portfolio New York, NY 14,27214.3k $439.7k $439.7k 0.00% Added +283 +283
85 Invesco Ltd. 0.00% of their portfolio ATLANTA, GA 13,84113.8k $426.4k $426.4k 0.00% Added +3.3k +3,342
86 STATE OF WISCONSIN INVESTMENT BOARD 0.00% of their portfolio MADISON, WI 13,76313.8k $424.0k $424.0k 0.00% Reduced -1.5k -1,549
87 CREDIT SUISSE AG/ 0.00% of their portfolio ZURICH, V8 12,89412.9k $397.3k $397.3k 0.00% Added +1.3k +1,264
88 Verition Fund Management LLC 0.01% of their portfolio GREENWICH, CT 12,34512.3k $380.3k $380.3k 0.01% New
89 HighTower Advisors, LLC 0.00% of their portfolio CHICAGO, IL 12,22612.2k $376.0k $376.0k 0.00% Added +654 +654
90 MANUFACTURERS LIFE INSURANCE COMPANY, THE 0.00% of their portfolio Toronto, A6 12,15612.2k $374.5k $374.5k 0.00% Added +480 +480
91 SG Americas Securities, LLC 0.00% of their portfolio NEW YORK, NY 11,96212.0k $369.0k $369.0k 0.00% Added +1.2k +1,206
92 Point72 Asset Management, L.P. 0.00% of their portfolio STAMFORD, CT 11,64111.6k $358.6k $358.6k 0.00% New
93 FEDERATED HERMES, INC. 0.00% of their portfolio PITTSBURGH, PA 10,74910.7k $331.2k $331.2k 0.00% Added +10.7k +10,745
94 LMR Partners LLP 0.01% of their portfolio LONDON, X0 10,20810.2k $314.5k $314.5k 0.01% New
95 PRINCIPAL FINANCIAL GROUP INC 0.00% of their portfolio DES MOINES, IA 9,9349.9k $306.1k $306.1k 0.00% Added +1.0k +1,033
96 Walleye Trading LLC 0.01% of their portfolio NEW YORK, NY 8,9929.0k $277.0k $277.0k 0.01% New
97 E Fund Management Co., Ltd. 0.02% of their portfolio GUANGZHOU, F4 8,0328.0k $247.0k $247.0k 0.02% New
98 MYDA Advisors LLC 0.10% of their portfolio WOODMERE, NY 8,0008.0k $246.5k $246.5k 0.10% Unchanged
99 Jasper Ridge Partners, L.P. 0.01% of their portfolio MENLO PARK, CA 7,8807.9k $242.8k $242.8k 0.01% Unchanged
100 Legal & General Group Plc 0.00% of their portfolio London, X0 7,1537.2k $220.4k $220.4k 0.00% Added +489 +489