Structured Product Labeling (SPL) is a document markup standard approved by the Health Level Seven (HL7) standards organization and adopted by the FDA as a mechanism for exchanging product and facility information. Product information provided by companies in SPL format may be accessed from the FDA Online Label Repository (labels.fda.gov) and the National Library of Medicine DailyMed web site (dailymed.nlm.nih.gov). FDA also maintains and publishes SPL Indexing Files for Pharmacologic Class, Substance, Product Concept, Biological Drug Substance, and Billing Units. Data from the Indexing Files can be linked to data in both SPL resources and external resources via chemical and non-chemical identifiers. In this talk we will present on the latest addition to SPL which allows indexing data on proteins, polymers and structurally diverse substances. We will also discuss the potential value of SPL to the integration between public chemistry databases, especially those hosted by the United States Government.