애로우헤드 파마슈티컬스, Inc.
US ˙ NasdaqGS ˙ US04280A1007

SecurityARWR / Arrowhead Pharmaceuticals, Inc.
InstitutionVanguard Group Inc
Latest Disclosed Ownership15,525,072 shares
Ownership 11.24%
Vanguard Group Inc ownership in ARWR / Arrowhead Pharmaceuticals, Inc.

2025-07-29 - Vanguard Group Inc has filed an SCHEDULE 13G/A form with the Securities and Exchange Commission (SEC) disclosing ownership of 15,525,072 shares of Arrowhead Pharmaceuticals, Inc. (US:ARWR). This represents 11.24 percent ownership of the company. In their previous filing dated 2024-04-10 , Vanguard Group Inc had reported owning 12,404,050 shares, indicating an increase of 25.16 percent.

Institutional Ownership: 13D/G Filings

This table shows a history of the 13D/G filings made by the investor and/or investor group. Note that the share values in this table are not directly comparable to any numbers shown in the 13F table (if any).

File
Date		Effective
Date		Form Prev
Shares		 Latest
Shares		 ΔShares
(Percent)		 Ownership
(Percent)		 ΔOwnership
(Percent)
2025-07-29 2025-07-29 13G/A 12,404,050 15,525,072 25.16 11.24 12.29
2024-04-10 2024-04-10 13G/A 10,672,076 12,404,050 16.23 10.01 0.81
2024-02-13 2024-02-13 13G/A 10,830,433 10,672,076 -1.46 9.93 -1.97
2023-06-09 2023-06-09 13G/A 10,286,172 10,830,433 5.29 10.13 4.43
2023-02-09 2023-02-09 13G/A 9,640,143 10,286,172 6.70 9.70 5.21
2022-02-09 2022-02-09 13G/A 9,281,551 9,640,143 3.86 9.22 2.10
2021-02-10 2021-02-10 13G/A 9,797,507 9,281,551 -5.27 9.03 -7.67
2020-02-12 2020-02-12 13G/A 10,844,571 9,797,507 -9.66 9.78 -13.98
2019-10-10 2019-10-10 13G 10,844,571 11.37

Important Note: One of the primary uses of the 13D/G filings is to evaluate the ability of a firm to control a company (ie, the "beneficial ownership"). To that end, firms are required to report not just direct holdings in companies, but indirect holdings that they control. For investment firms, these indirect holdings can include shares in funds they manage, advisory accounts, and in the case of activist campaigns, pledged votes. Therefore, share counts listed in 13D/G filings can differ significantly than share counts listed in 13F filings.

Institutional Ownership: 13F and NPORT Filings

The Security and Class in the table below are shown exactly as filed by the investor. We do our best to track continuity of investments through acquisitions, and this will be reflected in the table as changes in names. In addition to descriptive data, performance of the investment is shown over time. To calculate quarterly performance, we first calculate cost basis of the shares purchased during the quarter, then use that to calculate gross profit. Quarterly return is Gross Profit / Starting Portfolio value.

Note that cost basis is calculated and stored in thousands, so small quarterly changes in shares frequently result in a cost basis of zero.

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Disclosed Equity Positions (from 13F/NPORT Filings)
File
Date		 Effective
Date		Form Security Class ID Avg Price
Paid (Est)		 Reported
Shares		 ΔShares ΔShares
(%)		 Reported
Value
(x1000)		 ΔValue
(%)		 Alloc
(%)		 ΔAlloc ΔAlloc (%) Cost Basis
(x1000)		 Unrealized
Gain/Loss
(x1000)
2026-01-29 2025-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 15,293,121 -742,749 -4.63 1,015,310 83.57 0.0147
2025-11-07 2025-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 16,035,870 510,798 3.29 553,077 125.47 0.0083
2025-08-11 2025-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 15,525,072 2,322,510 17.59 245,296 45.84 0.0040
2025-05-09 2025-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 13,202,562 1,018,273 8.36 168,201 -26.57 0.0030
2025-02-11 2024-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 12,184,289 -44,766 -0.37 229,065 -3.30 0.0040
2024-11-13 2024-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 12,229,055 14,954 0.12 236,877 -25.38 0.0042
2024-08-13 2024-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 12,214,101 -189,949 -1.53 317,444 -10.52 0.0061
2024-05-10 2024-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 12,404,050 1,731,974 16.23 354,756 8.63 0.0070
2024-03-11 2023-12-31 13F/A-1 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,672,076 -186,239 -1.72 326,566 11.93 0.0071
2024-02-14 2023-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,672,076 -186,239 326,566 0.0062
2023-12-18 2023-09-30 13F/A-1 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,858,315 -113,415 -1.03 291,763 -25.43 0.0072
2023-11-14 2023-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,858,315 -113,415 291,763 0.0013
2023-08-14 2023-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,971,730 283,859 2.66 391,252 44.12 0.0093
2023-07-14 2023-03-31 13F/A-1 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,687,871 401,699 3.91 271,472 -34.93 0.0069
2023-05-15 2023-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,687,871 401,699 271,472 0.0069
2023-02-10 2022-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,286,172 140,182 1.38 417,207 24.42 0.0114
2022-11-14 2022-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,145,990 76,653 0.76 335,325 -5.42 0.0099
2022-08-12 2022-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,069,337 351,087 3.61 354,541 -20.67 0.0100
2022-05-13 2022-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,718,250 78,107 0.81 446,943 -30.07 0.0106
2022-02-14 2021-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,640,143 -3,773 -0.04 639,142 6.16 0.0145
2021-11-12 2021-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,643,916 4,852 0.05 602,069 -24.58 0.0150
2021-08-13 2021-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,639,064 37,927 0.40 798,307 25.39 0.0199
2021-05-14 2021-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,601,137 319,586 3.44 636,652 -10.60 0.0172
2021-02-12 2020-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,281,551 160,669 1.76 712,174 81.33 0.0207
2020-11-16 2020-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,120,882 -598,481 -6.16 392,745 -6.44 0.0130
2020-08-14 2020-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,719,363 90,837 0.94 419,779 51.54 0.0149
2020-05-15 2020-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,628,526 -168,981 -1.72 277,013 -55.43 0.0118
2020-02-14 2019-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 9,797,507 -1,047,064 -9.66 621,455 103.36 0.0212
2019-11-14 2019-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 10,844,571 2,206,733 25.55 305,600 33.51 0.0113
2019-08-14 2019-06-30 13F ARROWHEAD PHARMACEUTICALS COM 04280A100 8,637,838 3,712,392 75.37 228,903 153.26 0.0086
2019-05-15 2019-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 4,925,446 852,728 20.94 90,382 78.68 0.0035
2019-02-14 2018-12-31 13F ARROWHEAD PHARMACEUTICALS COM 04280A100 4,072,718 121,337 3.07 50,584 -33.22 0.0023
2018-12-13 2018-09-30 13F/A-2 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,951,381 10,273 0.26 75,748 41.32 0.0030
2018-11-23 2018-09-30 13F/A-1 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,951,381 0 75,748 0.0030
2018-11-14 2018-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,951,381 10,273 75,748
2018-08-14 2018-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,941,108 506,996 14.76 53,599 116.47 0.0022
2018-05-15 2018-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,434,112 561,640 19.55 24,760 134.25 0.0011
2018-02-14 2017-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,872,472 -19,793 -0.68 10,570 -15.60 0.0005
2017-11-14 2017-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,892,265 178,676 6.58 12,524 184.90 0.0006
2017-08-24 2017-06-30 13F/A-1 ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,713,589 -451,990 -14.28 4,396 -24.94 0.0002
2017-08-11 2017-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,713,589 -451,990 4,396
2017-05-12 2017-03-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 3,165,579 374,508 13.42 5,857 35.39 0.0003
2017-02-14 2016-12-31 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,791,071 307,862 12.40 4,326 -76.30 0.0002
2016-11-14 2016-09-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,483,209 36,863 1.51 18,252 40.24 0.0011
2016-08-10 2016-06-30 13F ARROWHEAD PHARMACEUTICALS IN COM 04280A100 2,446,346 2,446,346 13,015 0.0008
Legend
Shares
The total number of shares held by the institution at the end of the reporting period (the effective date). This is provided in the filing.
Value
The total value of the shares as of the effective date. This is provided in the filing.
Avg. Share Price
The weighted average share price of the shares held by the institution. We use FIFO accounting to determine this price
Class
This is the security class as indicated by the filer. There are a variety of values for this field. Common values include "EC" = equity common, "EP" - equity preferred
Allocation (%)
The percent of the institution's portfolio that this position represents. This is provided in NPORT filings. For 13F filings, we calculate it.
Change in Allocation
The change in allocation from the prior reporting period. This is calculated as current allocation - prior allocation.
Change in Allocation (%)
The percent change in allocation from the prior reporting period. This is calculated as (current allocation - prior allocation) / prior allocation.
Cost Basis
The total cost of the shares held. This is calculated as reported shares * avg. share price
Unrealized Gain/Loss
This is the market value of the position as of the effective date minus the cost basis.