# clm_E84D1B159AB1

subject: Regeneron Pharmaceuticals (/record/regeneron-pharmaceuticals.md)  
predicate: chair  
value: Leonard S. Schleifer  
valid_from: 2023-06-09  
valid_to: null  
published: 2023-04-17  
recorded: 2026-11-12  
confidence: 0.95  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-11-12  
cite: AsOf. "Regeneron Pharmaceuticals chair: Leonard S. Schleifer", as of 2023-06-09. Claim clm_E84D1B159AB1, https://asof.is/claim/clm_E84D1B159AB1, accessed 2026-11-12. Source: https://www.sec.gov/Archives/edgar/data/872589/000110465923045897/0001104659-23-045897-index.htm.  
checked: 2026-11-12 · its source page states the value and the date  

> Effective upon the expiration of Dr. Vagelos’s term, the Board plans to elect Leonard S. Schleifer, M.D., Ph.D., President and Chief Executive Officer of the Company, and George D. Yancopoulos, M.D., Ph.D., President and Chief Scientific Officer of the Company, as Co-Chairs of the Board

What https://www.sec.gov/Archives/edgar/data/872589/000110465923045897/0001104659-23-045897-index.htm says, word for word.

## Sources

- https://www.sec.gov/Archives/edgar/data/872589/000110465923045897/0001104659-23-045897-index.htm (primary, SEC EDGAR 8-K Item 5.02, published 2023-04-17)

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