Denison Mines Corp.
US ˙ NYSEAM ˙ CA2483561072

SecurityDNN / Denison Mines Corp.
InstitutionJanus Henderson Group Plc
Latest Disclosed Ownership1,882,979 shares
Latest Disclosed Value $ 6,651,962
Janus Henderson Group Plc reports 31.13% increase in ownership of DNN / Denison Mines Corp.

On May 18, 2026 - Janus Henderson Group Plc filed a 13F-HR/A form disclosing ownership of 1,882,979 shares of Denison Mines Corp. (US:DNN) valued at $6,646,916 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 17, 2026 disclosing 1,435,980 shares of Denison Mines Corp.. This represents a change in shares of 31.13% during the quarter. The current value of the position is $6,420,958 USD.

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)
2026-05-18 2026-03-31 13F/A-1 DENISON MINES COM 248356107 1,882,979 446,999 31.13 6,652 74.43 0.0011
2026-05-15 2026-03-31 13F DENISON MINES COM 248356107 1,574,357 138,377 9.64 5,562 45.84 0.0010
2026-02-17 2025-12-31 13F DENISON MINES COM 248356107 1,435,980 -86,475 -5.68 3,813 -9.08 0.0017
2025-11-14 2025-09-30 13F DENISON MINES COM 248356107 1,522,455 -2,038,731 -57.25 4,195 -35.58 0.0019
2025-08-14 2025-06-30 13F DENISON MINES COM 248356107 3,561,186 36,366 1.03 6,510 37.52 0.0032
2025-05-15 2025-03-31 13F DENISON MINES COM 248356107 3,524,820 256,904 7.86 4,735 -19.90 0.0026
2025-02-14 2024-12-31 13F DENISON MINES COM 248356107 3,267,916 -695,649 -17.55 5,911 -18.26 0.0030
2024-11-14 2024-09-30 13F DENISON MINES COM 248356107 3,963,565 647,046 19.51 7,230 8.71 0.0037
2024-08-14 2024-06-30 13F DENISON MINES COM 248356107 3,316,519 -1,610,690 -32.69 6,651 -31.51 0.0036
2024-05-15 2024-03-31 13F DENISON MINES COM 248356107 4,927,209 -448,292 -8.34 9,711 2.69 0.0053
2024-02-14 2023-12-31 13F DENISON MINES COM 248356107 5,375,501 1,153,956 27.33 9,458 34.31 0.0056
2023-11-14 2023-09-30 13F DENISON MINES COM 248356107 4,221,545 -2,662,630 -38.68 7,041 -18.04 0.0046
2023-08-14 2023-06-30 13F DENISON MINES COM 248356107 6,884,175 4,265,043 162.84 8,591 202.07 0.0053
2023-05-15 2023-03-31 13F DENISON MINES COM 248356107 2,619,132 -644,724 -19.75 2,845 -23.81 0.0019
2023-02-14 2022-12-31 13F DENISON MINES COM 248356107 3,263,856 3,263,856 3,734 0.0027
2021-02-16 2020-12-31 13F DENISON MINES COM 248356107 0 -523,174 -100.00 0 -100.00
2020-11-16 2020-09-30 13F DENISON MINES COM 248356107 523,174 523,174 219 0.0001
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.