Amgen Inc. (NASDAQ: AMGN, SEHK: 4332) is an international biotechnology company headquartered in Thousand Oaks, California. Amgen is the largest independent biotech firm, with approx. 15,000 staff members in 2005. Its products include EPOGEN, ARANESP, ENBREL, Kineret, Neulasta, NEUPOGEN, and Sensipar / Mimpara. EPOGEN and NEUPOGEN (the company's first products to hit the market) were the two most successful biopharmaceutical products at the time of their respective releases.

BusinessWeek (as cited in "References") ranked Amgen fourth on the S&P 500 for being the most "future-oriented" of those five hundred corporations. BusinessWeek ostensibly calculated the ratio of research and development spending, combined with capital spending, to total outlays; Amgen had the fourth highest ratio, at 506:1000. Amgen is the largest employer in Thousand Oaks and second only to the United States Navy in terms of number of people employed in Ventura County.