The XML document standard in which manufacturers submit drug labeling to the FDA; it is the source of prescribing information shown in drug databases.
An SPL carries the full label — indications, dosage and administration, contraindications, warnings, adverse reactions — plus structured product data such as ingredients, packaging and codes. Each submission replaces the previous version.
Because SPL is the submission format rather than a curated database, its text is the manufacturer's own labeling verbatim, including inconsistencies of style and capitalisation.