Regeneron Pharmaceuticals Sees Persistent Insider Share Sales Amid Strong Institutional Confidence.

### Regeneron Pharmaceuticals Sees Continued Insider Trading Amidst Stock Movements

As of May 30, 2025, insider trading activity at Regeneron Pharmaceuticals, Inc. (NASDAQ: REGN) remains active, reflecting a dynamic trend in the company's stock transactions. In the past month, significant insider sales have been recorded, aligning with broader corporate trends observed over the last year.

#### Recent Insider Trading Activities

In May 2025, the trend of insider trading at Regeneron witnessed notable activities. On May 30, insider activities revealed multiple transactions primarily consisting of stock awards and conversions of derivative securities. Noteworthy insiders such as Joseph La Rosa, General Counsel, and other directors received significant stock awards without cash consideration.

However, the most eye-catching transactions involved sales of substantial shares. Notably, during April, several insiders executed prominent sales, marking a continued trend of divestment from insider-held shares. For instance, Christopher R. Fenimore, the Chief Financial Officer, executed transactions resulting in proceeds of approximately $6.84 million in share sales.

#### Yearly Insider Trends

Over the past 12 months, Regeneron's regulatory filings show a total of 66 insider transactions. These actions involved a mixture of stock awards, gifts, conversions of derivative securities, and several large sales at fluctuating stock prices. Among the significant transactions, Marion E. McCourt, an Officer at Regeneron, sold shares valued over a million dollars several times between October and November 2024, following earlier sales by other top executives, including Leonard S. Schleifer, the Chief Executive Officer.

While most transactions involved stock grants at zero cost, indicating compensatory strategy for the company's leadership, the frequent insider sales could attract investor scrutiny. Insiders, collectively, hold a small percentage, approximately 1.9%, of Regeneron's total available shares, underscoring a broader institutional presence in the shareholder base.

#### Institutional and Mutual Fund Holdings

Institutional investors dominate Regeneron's ownership landscape, with prominent entities like Vanguard Group Inc and BlackRock Inc holding substantial shares. As of March 31, 2025, institutions possessed around 92% of the company's stock, showcasing strong confidence in Regeneron's future prospects among institutional stakeholders. Mutual funds such as the Vanguard Total Stock Market Index Fund also hold significant positions, reflecting widespread institutional interest.

#### Conclusion

Regeneron Pharmaceuticals' insiders have engaged in active trading throughout the past month, with notable sales continuing to highlight the transactional landscape. While predominantly featuring stock awards and derivative security conversions, the insider sales volume suggests a strategic realignment or profit-taking amidst fluctuating market conditions. Institutional holders persist in their robust engagement with Regeneron, indicative of ongoing trust in the pharmaceutical giant's long-term growth potential despite insider trading volatility.