The mechanics are lot control and genealogy: incoming material certs tied to lot numbers, lot numbers tied to work orders, work orders tied to serialized units, producing an as-built record alongside the as-designed bill of materials. Granularity is the main cost lever. Lot-level tracking is cheap and answers most questions; unit-level serialization costs more and is reserved for safety-critical or high-value parts.

Three forces keep raising the bar. Recalls: regulators and customers expect fast, narrow containment. Compliance: conflict minerals rules and forced-labor enforcement such as UFLPA require importers to document where material originated, several tiers up. Counterfeits: electronics and aerospace buyers trace provenance because a re-marked chip or an uncertified fastener is invisible to ordinary incoming inspection.

Traceability is distinct from track and trace, which follows shipments through logistics networks; traceability follows material identity through production. It is also only as good as the weakest tier: if a sub-supplier blends lots, the genealogy breaks there. LightSource keeps part, supplier, and BOM relationships connected in one system, which gives sourcing teams the data backbone a traceability program builds on.