iShares Biotechnology ETF

iShares Biotechnology ETF (IBB) is a passively managed fund issued by iShares, the ETF franchise of BlackRock, the world's largest asset manager. It tracks the ICE Biotechnology Index, a modified market-cap-weighted benchmark of U.S.-listed biotechnology and pharmaceutical companies, holding roughly 260 names. IBB is the broad Healthspan "intervene" lens: its mapped positions include Gilead, Amgen, Vertex, Moderna, Regeneron, Illumina, Alnylam, and United Therapeutics, alongside the tools-and-services names (Natera, Charles River, Medpace, Bio-Techne) that serve therapeutic development. In the PXS map, IBB is the machine's broadest public-fund expression of the Healthspan universe's therapeutic layer, distinguished from ARKG by its passive, cap-weighted breadth rather than a thesis-driven concentration. Coverage is limited to direct, issuer-reported positions in already-mapped companies, not the complete portfolio, and this is a research map rather than a recommendation. IBB is most useful for seeing where the largest biotech vehicle's index weight lands across the mapped Healthspan companies. Its largest mapped positions are Gilead (8.36%), Amgen (7.81%), Vertex (7.58%), and Moderna (5.89%), with Natera, Illumina, Alnylam, and United Therapeutics carrying additional mapped weight across therapeutics, sequencing, and diagnostics.