Regeneron Pharmaceuticals, Inc.
MX ˙ BMV ˙ US75886F1075
SecurityMX:REGN / Regeneron Pharmaceuticals, Inc.
InstitutionRhumbline Advisers
Latest Disclosed Ownership157,781 shares
Latest Disclosed Value $ 121,907,836
Rhumbline Advisers reports 1.88% decrease in ownership of REGN / Regeneron Pharmaceuticals, Inc.

On May 12, 2026 - Rhumbline Advisers filed a 13F-HR form disclosing ownership of 157,781 shares of Regeneron Pharmaceuticals, Inc. (MX:REGN) valued at $121,907,836 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 160,805 shares of Regeneron Pharmaceuticals, Inc.. This represents a change in shares of -1.88% 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)
2026-05-12 2026-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 157,781 -3,024 -1.88 121,908 -1.78 0.1043
2026-02-13 2025-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 160,805 -7,196 -4.28 124,120 31.40 0.1003
2025-11-06 2025-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 168,001 -2,658 -1.56 94,462 5.43 0.0759
2025-08-12 2025-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 170,659 -2,508 -1.45 89,596 -18.42 0.0767
2025-05-29 2025-03-31 13F/A-1 REGENERON PHARMACEUTICALS COM COM 75886F107 173,167 2,547 1.49 109,828 -9.63 0.1027
2025-04-08 2025-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 173,167 2,547 109,828 0.1027
2025-05-29 2024-12-31 13F/A-1 REGENERON PHARMACEUTICALS COM COM 75886F107 170,620 -4,126 -2.36 121,538 -33.84 0.1087
2025-01-30 2024-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 170,620 -4,126 121,538 0.1087
2024-11-12 2024-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 174,746 -5,351 -2.97 183,700 -2.95 0.1657
2024-08-01 2024-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 180,097 -3,470 -1.89 189,287 7.13 0.1779
2024-05-09 2024-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 183,567 1,969 1.08 176,681 10.78 0.1697
2024-02-08 2023-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 181,598 -1,680 -0.92 159,496 5.74 0.1672
2023-11-09 2023-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 183,278 -2,795 -1.50 150,830 12.81 0.1751
2023-08-08 2023-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 186,073 2,369 1.29 133,701 89,033.33 0.1498
2023-05-11 2023-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 183,704 -4,201 -2.24 151 -99.89 0.1862
2023-02-14 2022-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 187,905 8,907 4.98 135,572 9.95 0.1822
2022-11-10 2022-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 178,998 5,425 3.13 123,306 20.18 0.1837
2022-08-11 2022-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 173,573 10,447 6.40 102,604 -9.94 0.1497
2022-05-12 2022-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 163,126 1,127 0.70 113,930 11.36 0.1466
2022-02-10 2021-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 161,999 732 0.45 102,306 4.83 0.1254
2021-11-12 2021-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 161,267 -525 -0.32 97,596 8.00 0.1321
2021-08-05 2021-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 161,792 -3,458 -2.09 90,367 15.58 0.1186
2021-05-06 2021-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 165,250 -8,624 -4.96 78,186 -6.92 0.1062
2021-02-10 2020-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 173,874 -19,004 -9.85 84,000 -22.20 0.1159
2020-11-12 2020-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 192,878 -3,019 -1.54 107,969 -11.62 0.1692
2020-08-13 2020-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 195,897 49,448 33.76 122,171 70.84 0.2040
2020-05-06 2020-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 146,449 387 0.26 71,510 30.39 0.1499
2020-02-05 2019-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 146,062 4,581 3.24 54,843 39.74 0.0917
2019-10-23 2019-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 141,481 6,372 4.72 39,247 -7.19 0.0717
2019-08-14 2019-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 135,109 2,289 1.72 42,289 -22.46 0.0794
2019-05-01 2019-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 132,820 -14,415 -9.79 54,539 -0.82 0.1056
2019-01-31 2018-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 147,235 1,104 0.76 54,992 -6.86 0.1197
2018-11-07 2018-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 146,131 -1,338 -0.91 59,043 16.06 0.1140
2018-08-06 2018-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 147,469 4,098 2.86 50,875 3.05 0.1026
2018-05-02 2018-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 143,371 148 0.10 49,371 -8.31 0.1031
2018-02-09 2017-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 143,223 7,939 5.87 53,846 -10.98 0.1094
2017-11-06 2017-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 135,284 2,030 1.52 60,488 -7.58 0.1315
2017-08-02 2017-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 133,254 2,122 1.62 65,446 28.79 0.1494
2017-05-02 2017-03-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 131,132 2,824 2.20 50,815 7.89 0.1187
2017-01-27 2016-12-31 13F REGENERON PHARMACEUTICALS COM COM 75886F107 128,308 2,179 1.73 47,101 -7.11 0.1194
2016-11-08 2016-09-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 126,129 3,200 2.60 50,706 18.11 0.1397
2016-08-11 2016-06-30 13F REGENERON PHARMACEUTICALS COM COM 75886F107 122,929 4,439 3.75 42,930 0.52 0.1272
2016-05-02 2016-03-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 118,490 4,356 3.82 42,709 -31.07 0.1325
2016-02-03 2015-12-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 114,134 2,873 2.58 61,960 19.72 0.1994
2015-11-04 2015-09-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 111,261 3,596 3.34 51,752 -5.77 0.1761
2015-08-04 2015-06-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 107,665 -19,126 -15.08 54,923 -4.05 0.1751
2015-05-12 2015-03-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 126,791 -1,386 -1.08 57,244 8.86 0.1651
2015-02-06 2014-12-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 128,177 -3,381 -2.57 52,585 10.87 0.1528
2014-11-12 2014-09-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 131,558 -4,946 -3.62 47,429 23.01 0.1425
2014-08-06 2014-06-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 136,504 -4,249 -3.02 38,558 -8.77 0.1132
2014-05-06 2014-03-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 140,753 931 0.67 42,265 9.82 0.1254
2014-02-03 2013-12-31 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 139,822 -2,800 -1.96 38,485 -13.75 0.1135
2013-11-05 2013-09-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 142,622 -2,226 -1.54 44,622 36.99 0.1383
2013-08-07 2013-06-30 13F REGENERON PHARMACEUTICALS COMM COM 75886F107 144,848 144,848 32,573 0.1047
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.