Should You Be Excited for Regeneron (REGN)?

Core Insights - Longleaf Partners Fund returned 3.35% in Q4 2025, outperforming the S&P 500's 2.66% but underperforming the Russell 1000 Value Index's 3.81% [1] - The firm faced challenges in 2025, with only 5% of the portfolio gaining 20% or more compared to 35% of the S&P 500 [1] - The firm emphasizes strengthening portfolio outcomes over chasing short-term winners, advocating for a focus on real companies during speculative periods [1] Company Focus: Regeneron Pharmaceuticals, Inc. - Regeneron Pharmaceuticals, Inc. had a one-month return of -5.94% and a 52-week gain of 7.55%, with a market capitalization of $77.693 billion [2] - Initially a detractor, Regeneron became a contributor in Q4 2025, with a phased buy-in strategy proving effective [3] - The company is well-positioned in allergic diseases and oncology, with a focus on its pipeline value rather than just EYLEA, which constitutes less than 20% of its value [3] - Regeneron has a net cash balance sheet, strong owner-partners, and has avoided large M&A, opting for significant share repurchases in 2025 [3]