Regeneron Pharmaceuticals, Inc.
MX ˙ BMV ˙ US75886F1075
SecurityMX:REGN / Regeneron Pharmaceuticals, Inc.
InstitutionClearbridge Investments, LLC
Latest Disclosed Ownership73,792 shares
Latest Disclosed Value $ 57,014,651
Clearbridge Investments, LLC reports 18.96% increase in ownership of REGN / Regeneron Pharmaceuticals, Inc.

On May 13, 2026 - Clearbridge Investments, LLC filed a 13F-HR form disclosing ownership of 73,792 shares of Regeneron Pharmaceuticals, Inc. (MX:REGN) valued at $57,014,651 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 11, 2026 disclosing 62,031 shares of Regeneron Pharmaceuticals, Inc.. This represents a change in shares of 18.96% 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)
2026-05-13 2026-03-31 13F Regeneron Pharmaceuticals COM 75886F107 73,792 11,761 18.96 57,015 19.08 0.0447
2026-02-11 2025-12-31 13F Regeneron Pharmaceuticals COM 75886F107 62,031 -2,695 -4.16 47,880 31.56 0.0383
2025-11-13 2025-09-30 13F Regeneron Pharmaceuticals COM 75886F107 64,726 52,881 446.44 36,393 485.28 0.0274
2025-08-12 2025-06-30 13F Regeneron Pharmaceuticals COM 75886F107 11,845 5,121 76.16 6,219 45.83 0.0050
2025-05-13 2025-03-31 13F Regeneron Pharmaceuticals COM 75886F107 6,724 2,746 69.03 4,265 50.51 0.0037
2025-02-12 2024-12-31 13F Regeneron Pharmaceuticals COM 75886F107 3,978 26 0.66 2,834 -31.80 0.0023
2024-11-12 2024-09-30 13F Regeneron Pharmaceuticals COM 75886F107 3,952 2,519 175.79 4,154 175.83 0.0033
2024-08-27 2024-06-30 13F/A-1 Regeneron Pharmaceuticals COM 75886F107 1,433 1,433 1,506 0.0012
2020-11-12 2020-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -80 -100.00 0 -100.00
2020-08-14 2020-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 80 80 50 0.0000
2019-08-14 2019-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -118,775 -100.00 0 -100.00
2019-05-15 2019-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 118,775 -759,190 -86.47 48,771 -85.13 0.0431
2019-02-14 2018-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 877,965 6,274 0.72 327,920 -6.89 0.3317
2018-11-28 2018-09-30 13F/A-1 REGENERON PHARMACEUTICALS COM 75886F107 871,691 -4,638 -0.53 352,198 16.50 0.3031
2018-11-14 2018-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 871,691 -4,638 352,198
2018-08-14 2018-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 876,329 36,177 4.31 302,325 4.50 0.2475
2018-05-15 2018-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 840,152 33,390 4.14 289,315 -4.61 0.2730
2018-02-14 2017-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 806,762 47,010 6.19 303,310 -10.71 0.2802
2017-11-14 2017-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 759,752 29,181 3.99 339,700 -5.33 0.3267
2017-08-14 2017-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 730,571 40,317 5.84 358,813 34.15 0.3526
2017-06-07 2017-03-31 13F/A-1 REGENERON PHARMACEUTICALS COM 75886F107 690,254 245,531 55.21 267,480 63.84 0.2691
2017-05-15 2017-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 690,254 267,480
2017-02-14 2016-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 444,723 116,480 35.49 163,253 23.71 0.1794
2016-11-14 2016-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 328,243 26,151 8.66 131,960 25.08 0.1486
2016-08-15 2016-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 302,092 21,667 7.73 105,500 4.38 0.1247
2016-05-16 2016-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 280,425 96,330 52.33 101,076 1.14 0.1207
2016-02-16 2015-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 184,095 7,859 4.46 99,939 21.92 0.1157
2015-11-16 2015-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 176,236 -18,505 -9.50 81,974 -17.48 0.0981
2015-08-17 2015-06-30 13F/A-1 REGENERON PHARMACEUTICALS COM 75886F107 194,741 12,161 6.66 99,343 20.52 0.1050
2015-08-14 2015-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 194,741 99,343
2015-05-15 2015-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 182,580 2,990 1.66 82,431 11.88 0.0856
2015-02-17 2014-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 179,590 -978 -0.54 73,677 13.18 0.0775
2014-11-14 2014-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 180,568 137,837 322.57 65,098 439.34 0.0717
2014-08-14 2014-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 42,731 39,939 1,430.48 12,070 1,340.33 0.0136
2014-05-15 2014-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 2,792 -254 -8.34 838 0.00 0.0010
2014-02-14 2013-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 3,046 635 26.34 838 11.14 0.0010
2013-11-14 2013-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 2,411 -602 -19.98 754 11.21 0.0011
2013-08-14 2013-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 3,013 3,013 678 0.0010
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.