Affymetrix, Inc. was an American company that manufactured DNA microarrays; it was based in Santa Clara, California, United States. The company was acquired by Thermo Fisher Scientific in March 2016. The company was founded by Stephen Fodor in 1992. It began as a unit in Affymax N.V. in 1991 by Fodor's group, which had in the late 1980s developed methods for fabricating DNA microarrays, called "GeneChip" according to the Affymetrix trademark, using semiconductor manufacturing techniques. The company's first product, an HIV genotyping GeneChip, was introduced in 1994 and the company went public in 1996. As a result of its pioneering work and the ensuing popularity of microarray products, Affymetrix derived significant benefit from its patent portfolio in this area.