Regeneron Pharmaceuticals, Inc.
MX ˙ BMV ˙ US75886F1075
SecurityMX:REGN / Regeneron Pharmaceuticals, Inc.
InstitutionParnassus Investments /ca
Latest Disclosed Ownership97,495 shares
Latest Disclosed Value $ 75,328,537
Parnassus Investments /ca reports 0.98% increase in ownership of REGN / Regeneron Pharmaceuticals, Inc.

On May 12, 2026 - Parnassus Investments /ca filed a 13F-HR form disclosing ownership of 97,495 shares of Regeneron Pharmaceuticals, Inc. (MX:REGN) valued at $75,328,537 USD as of March 31, 2026. The entity filed a previous 13F-HR on February 12, 2026 disclosing 96,545 shares of Regeneron Pharmaceuticals, Inc.. This represents a change in shares of 0.98% 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.

Upgrade to unlock premium data and export to Excel .

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 75886F107 97,495 950 0.98 75,329 1.08 0.2206
2026-02-12 2025-12-31 13F REGENERON PHARMACEUTICALS COM 75886F107 96,545 -4,478 -4.43 74,520 31.19 0.1933
2025-10-24 2025-09-30 13F REGENERON PHARMACEUTICALS COM 75886F107 101,023 -61 -0.06 56,802 7.03 0.1313
2025-08-06 2025-06-30 13F REGENERON PHARMACEUTICALS COM 75886F107 101,084 101,084 53,069 0.1224
2020-05-01 2020-03-31 13F Regeneron Pharmaceuticals COMMON STOCK 75886F107 0 -145,000 -100.00 0 -100.00
2020-02-13 2019-12-31 13F Regeneron Pharmaceuticals COMMON STOCK 75886F107 145,000 -480,000 -76.80 54,445 -68.60 0.1833
2019-10-29 2019-09-30 13F Regeneron Pharmaceuticals COMMON STOCK 75886F107 625,000 0 0.00 173,375 -11.37 0.6284
2019-08-08 2019-06-30 13F Regeneron Pharmaceuticals COMMON STOCK 75886F107 625,000 465,000 290.62 195,625 197.76 0.7404
2019-05-01 2019-03-31 13F Regeneron Pharmaceuticals COMMON STOCK 75886F107 160,000 160,000 65,699 0.2591
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.