Amgen Inc.
CH ˙ SWX ˙ NL0000888691
SecurityCH:AMGN / Amgen Inc.
InstitutionTAGStone Capital, Inc.
Latest Disclosed Ownership4,155 shares
Latest Disclosed Value $ 1,461,932
TAGStone Capital, Inc. reports 0.63% increase in ownership of AMGN / Amgen Inc.

On May 11, 2026 - TAGStone Capital, Inc. filed a 13F-HR form disclosing ownership of 4,155 shares of Amgen Inc. (CH:AMGN) valued at $1,461,932 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 10, 2026 disclosing 4,129 shares of Amgen Inc.. This represents a change in shares of 0.63% during the quarter.

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)
2026-05-11 2026-03-31 13F AMGEN COM 031162100 4,155 26 0.63 1,462 8.14 0.5169
2026-02-10 2025-12-31 13F AMGEN COM 031162100 4,129 28 0.68 1,351 16.77 0.5034
2025-11-05 2025-09-30 13F AMGEN COM 031162100 4,101 32 0.79 1,157 -1.28 0.4585
2025-08-11 2025-06-30 13F AMGEN COM 031162100 4,069 331 8.86 1,173 117,100.00 0.4838
2025-05-05 2025-03-31 13F AMGEN COM 031162100 3,738 27 0.73 1 0.5731
2025-02-11 2024-12-31 13F AMGEN COM 031162100 3,711 30 0.81 1 -100.00 0.4759
2024-11-08 2024-09-30 13F AMGEN COM 031162100 3,681 25 0.68 1 0.00 0.6059
2024-08-13 2024-06-30 13F AMGEN COM 031162100 3,656 39 1.08 1 0.00 0.6475
2024-05-07 2024-03-31 13F AMGEN COM 031162100 3,617 30 0.84 1 0.00 0.6020
2024-02-12 2023-12-31 13F AMGEN COM 031162100 3,587 28 0.79 1 0.6753
2023-11-09 2023-09-30 13F AMGEN COM 031162100 3,559 28 0.79 1 0.7036
2023-08-10 2023-06-30 13F AMGEN COM 031162100 3,531 34 0.97 1 0.5652
2023-05-11 2023-03-31 13F AMGEN COM 031162100 3,497 32 0.92 1 0.6324
2023-02-13 2022-12-31 13F AMGEN COM 031162100 3,465 24 0.70 1 -100.00 0.7509
2022-11-01 2022-09-30 13F AMGEN COM 031162100 3,441 27 0.79 776 -6.62 0.7205
2022-08-01 2022-06-30 13F AMGEN COM 031162100 3,414 26 0.77 831 1.47 0.7922
2022-05-13 2022-03-31 13F AMGEN COM 031162100 3,388 28 0.83 819 8.33 0.6906
2022-02-01 2021-12-31 13F AMGEN COM 031162100 3,360 3,360 756 0.6286
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.