Regeneron Pharmaceuticals, Inc.
US ˙ NasdaqGS ˙ US75886F1075

SecurityREGN / Regeneron Pharmaceuticals, Inc.
InstitutionWalleye Capital LLC
Latest Disclosed Ownership4,022 shares
Latest Disclosed Value $ 3,107,558
Walleye Capital LLC ownership in REGN / Regeneron Pharmaceuticals, Inc.

On May 13, 2026 - Walleye Capital LLC filed a 13F-HR/A form disclosing ownership of 4,022 shares of Regeneron Pharmaceuticals, Inc. (US:REGN) valued at $3,107,558 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 13, 2026 disclosing 35,500 shares of Regeneron Pharmaceuticals, Inc.. This represents a change in shares of -88.67% during the quarter. The current value of the position is $2,555,780 USD.

Walleye Capital LLC has a history of taking positions in derivatives of the underlying security (REGN) in the form of stock options. The firm currently holds call options representing 1,200 of underlying shares valued at $927,168 USD and put options representing 500 of underlying shares valued at $386,320 USD .

Note: prior versions of this page mistakenly stated that the share values represented the number of options, not the number of underlying shares. For more information on the data backing these reports, please see the SEC document Frequently Asked Questions About Form 13F.

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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Institutional Put/Call Ratios
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In addition to reporting standard equity and debt issues, institutions with more than 100MM assets under management must also disclose their put and call option holdings. Since put options generally indicate negative sentiment, and call options indicate positive sentiment, we can get a sense of the overall institutional sentiment by plotting the ratio of puts to calls. The chart to the right plots the historical put/call ratio for this instrument.

Using Put/Call Ratio as an indicator of investor sentiment overcomes one of the key deficiencies of using total institutional ownership, which is that a significant amount of assets under management are invested passively to track indices. Passively-managed funds do not typically buy options, so the put/call ratio indicator more closely tracks the sentiment of actively-managed funds.

REGN / Regeneron Pharmaceuticals, Inc. Historical Put/Call Ratio
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/A-1 REGENERON PHARMACEUTICALS COM 75886F107 4,022 -31,478 -88.67 3,108 -88.66 0.0129
2026-05-08 2026-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 4,022 -31,478 3,108 0.0129
2026-02-13 2025-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 35,500 -51,974 -59.42 27,401 -44.29 0.0841
2025-11-14 2025-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 87,474 25,703 41.61 49,184 51.67 0.1845
2025-08-13 2025-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 61,771 53,575 653.67 32,430 523.87 0.1260
2025-05-14 2025-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 8,196 -1,878 -18.64 5,198 -27.56 0.0235
2025-02-13 2024-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 10,074 2,807 38.63 7,176 -6.06 0.0175
2024-11-14 2024-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 7,267 2,367 48.31 7,639 48.33 0.0159
2024-08-14 2024-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 4,900 425 9.50 5,150 19.57 0.0092
2024-05-15 2024-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 4,475 2,425 118.29 4,307 139.28 0.0077
2024-02-14 2023-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 2,050 2,050 1,800 0.0038
2023-11-21 2023-09-30 13F/A-1 REGENERON PHARMACEUTICALS COM 75886F107 0 -21,673 -100.00 0 -100.00
2023-11-14 2023-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -21,673 0
2023-08-14 2023-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 21,673 21,473 10,736.50 15,573 9,395.12 0.0564
2023-05-15 2023-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 200 200 164 0.0025
2021-11-15 2021-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -3,415 -100.00 0 -100.00
2021-08-16 2021-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 3,415 3,415 1,907 0.0650
2021-02-16 2020-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -589 -100.00 0 -100.00
2020-11-16 2020-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 589 589 330 0.0368
2020-08-14 2020-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 0 -468 -100.00 0 -100.00
2020-05-15 2020-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 468 78 20.00 228 56.16 0.0502
2020-02-14 2019-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 390 380 3,800.00 146 4,766.67 0.0095
2019-11-14 2019-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 10 0 0.00 3 0.00 0.0002
2019-08-14 2019-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 10 -443 -97.79 3 -98.39 0.0003
2019-08-14 2019-03-31 13F/A-1 REGENERON PHARMACEUTICALS COM 75886F107 453 453 186 0.0306
2019-05-15 2019-03-31 13F REGENERON PHARMACEUTICALS COM 75886F107 453 186 0.0306
Disclosed Call Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share
Price
Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-13 2026-03-31 13F/A REGENERON PHARMACEUTICALS COM Call 1,200 -68.42 927 -68.39 n/a n/a n/a
2026-05-08 2026-03-31 13F REGENERON PHARMACEUTICALS COM Call 1,200 927 n/a n/a n/a
2026-02-13 2025-12-31 13F REGENERON PHARMACEUTICALS COM Call 3,800 2.70 2,933 41.01 n/a n/a n/a
2025-11-14 2025-09-30 13F REGENERON PHARMACEUTICALS COM Call 3,700 -55.95 2,080 -52.83 n/a n/a n/a
2025-08-13 2025-06-30 13F REGENERON PHARMACEUTICALS COM Call 8,400 37.70 4,410 14.01 n/a n/a n/a
2025-05-14 2025-03-31 13F REGENERON PHARMACEUTICALS COM Call 6,100 -25.61 3,869 -33.78 n/a n/a n/a
2025-02-13 2024-12-31 13F REGENERON PHARMACEUTICALS COM Call 8,200 1.23 5,841 -31.40 n/a n/a n/a
2024-11-14 2024-09-30 13F REGENERON PHARMACEUTICALS COM Call 8,100 0.00 8,515 0.02 n/a n/a n/a
2024-08-14 2024-06-30 13F REGENERON PHARMACEUTICALS COM Call 8,100 -42.55 8,513 -37.27 n/a n/a n/a
2024-05-15 2024-03-31 13F REGENERON PHARMACEUTICALS COM Call 14,100 327.27 13,571 368.29 n/a n/a n/a
2024-02-14 2023-12-31 13F REGENERON PHARMACEUTICALS COM Call 3,300 -66.33 2,898 -64.07 n/a n/a n/a
2023-11-21 2023-09-30 13F/A REGENERON PHARMACEUTICALS COM Call 9,800 50.77 8,065 72.70 n/a n/a n/a
2023-11-14 2023-09-30 13F REGENERON PHARMACEUTICALS COM Call 9,800 8,065 n/a n/a n/a
2023-08-14 2023-06-30 13F REGENERON PHARMACEUTICALS COM Call 6,500 1.56 4,671 -11.18 n/a n/a n/a
2023-05-15 2023-03-31 13F REGENERON PHARMACEUTICALS COM Call 6,400 2,033.33 5,259 2,334.26 n/a n/a n/a
2023-02-14 2022-12-31 13F REGENERON PHARMACEUTICALS COM Call 300 0.00 216 4.35 n/a n/a n/a
2022-11-14 2022-09-30 13F REGENERON PHARMACEUTICALS COM Call 300 207 n/a n/a n/a
2020-05-15 2020-03-31 13F REGENERON PHARMACEUTICALS COM Call 0 -100.00 0 -100.00 n/a n/a n/a
2020-02-14 2019-12-31 13F REGENERON PHARMACEUTICALS COM Call 4,500 -87.29 1,690 -82.79 n/a n/a n/a
2019-11-14 2019-09-30 13F REGENERON PHARMACEUTICALS COM Call 35,400 221.82 9,820 185.22 n/a n/a n/a
2019-08-14 2019-06-30 13F REGENERON PHARMACEUTICALS COM Call 11,000 69.23 3,443 29.00 n/a n/a n/a
2019-08-14 2019-03-31 13F/A REGENERON PHARMACEUTICALS COM Call 6,500 2,669 n/a n/a n/a
2019-05-15 2019-03-31 13F REGENERON PHARMACEUTICALS COM Call 6,500 2,669 n/a n/a n/a
Disclosed Put Options
File
Date
Effective
Date
Form Security Class ID Opt Avg Share Price Shares ΔShares
(%)
Value
(x1000)
ΔValue
(%)
Prior Allocation
(%)
Allocation
(%)
ΔAllocation
(%)
Cost Basis
(x1000)
Profit
(x1000)
Return
(%)
2026-05-13 2026-03-31 13F/A REGENERON PHARMACEUTICALS COM Put 500 -95.97 386 -95.97 n/a n/a n/a
2026-05-08 2026-03-31 13F REGENERON PHARMACEUTICALS COM Put 500 386 n/a n/a n/a
2026-02-13 2025-12-31 13F REGENERON PHARMACEUTICALS COM Put 12,400 125.45 9,571 209.54 n/a n/a n/a
2025-11-14 2025-09-30 13F REGENERON PHARMACEUTICALS COM Put 5,500 -48.60 3,092 -44.95 n/a n/a n/a
2025-08-13 2025-06-30 13F REGENERON PHARMACEUTICALS COM Put 10,700 91.07 5,618 58.18 n/a n/a n/a
2025-05-14 2025-03-31 13F REGENERON PHARMACEUTICALS COM Put 5,600 -61.38 3,552 -65.62 n/a n/a n/a
2025-02-13 2024-12-31 13F REGENERON PHARMACEUTICALS COM Put 14,500 35.51 10,329 -8.18 n/a n/a n/a
2024-11-14 2024-09-30 13F REGENERON PHARMACEUTICALS COM Put 10,700 -29.61 11,248 -29.59 n/a n/a n/a
2024-08-14 2024-06-30 13F REGENERON PHARMACEUTICALS COM Put 15,200 -23.23 15,976 -16.17 n/a n/a n/a
2024-05-15 2024-03-31 13F REGENERON PHARMACEUTICALS COM Put 19,800 115.22 19,057 135.85 n/a n/a n/a
2024-02-14 2023-12-31 13F REGENERON PHARMACEUTICALS COM Put 9,200 -27.56 8,080 -22.69 n/a n/a n/a
2023-11-21 2023-09-30 13F/A REGENERON PHARMACEUTICALS COM Put 12,700 1,170.00 10,452 1,355.57 n/a n/a n/a
2023-11-14 2023-09-30 13F REGENERON PHARMACEUTICALS COM Put 12,700 10,452 n/a n/a n/a
2023-08-14 2023-06-30 13F REGENERON PHARMACEUTICALS COM Put 1,000 -47.37 719 -54.00 n/a n/a n/a
2023-05-15 2023-03-31 13F REGENERON PHARMACEUTICALS COM Put 1,900 533.33 1,561 622.69 n/a n/a n/a
2023-02-14 2022-12-31 13F REGENERON PHARMACEUTICALS COM Put 300 -78.57 216 -77.59 n/a n/a n/a
2022-11-14 2022-09-30 13F REGENERON PHARMACEUTICALS COM Put 1,400 964 n/a n/a n/a
2020-08-14 2020-06-30 13F REGENERON PHARMACEUTICALS COM Put 0 -100.00 0 -100.00 n/a n/a n/a
2020-05-15 2020-03-31 13F REGENERON PHARMACEUTICALS COM Put 400 -94.20 195 -92.47 n/a n/a n/a
2020-02-14 2019-12-31 13F REGENERON PHARMACEUTICALS COM Put 6,900 -40.52 2,591 -19.48 n/a n/a n/a
2019-11-14 2019-09-30 13F REGENERON PHARMACEUTICALS COM Put 11,600 866.67 3,218 755.85 n/a n/a n/a
2019-08-14 2019-06-30 13F REGENERON PHARMACEUTICALS COM Put 1,200 -47.83 376 -60.17 n/a n/a n/a
2019-08-14 2019-03-31 13F/A REGENERON PHARMACEUTICALS COM Put 2,300 944 n/a n/a n/a
2019-05-15 2019-03-31 13F REGENERON PHARMACEUTICALS COM Put 2,300 944 n/a n/a n/a
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.