LOT
LOT denotes the batch or production lot number of a product. The symbol is standardised in ISO 15223-1 and must appear on medical device labels under MDR (EU) 2017/745. All units bearing the same LOT number were produced under identical or equivalent conditions.
In the event of a product defect or safety recall, the LOT number enables rapid identification of all affected units throughout the supply chain. This is why LOT documentation is a core element of any quality management system in healthcare distribution and hospital procurement.
Together with REF (product reference), LOT forms the cornerstone of product traceability. For stock management, the FEFO principle (First Expired, First Out) applies: batches with earlier expiry dates must be used first, with LOT numbers used to manage stock rotation.
In the UDI system under MDR, the LOT is part of the Production Identifier (PI), distinct from the Device Identifier (DI), which is tied to the REF.
Frequently asked questions
Why is the LOT number mandatory on medical devices?
The LOT number enables traceability of all units in a production batch. In a safety recall, it allows rapid identification and removal of all affected products. Mandatory under MDR (EU) 2017/745.
What is the difference between LOT and REF?
REF identifies the product model (article number); LOT identifies the specific production batch. A product always has a fixed REF but changing LOT numbers with each production run.
How long must LOT records be retained?
Under MDR (EU) 2017/745 Art. 10(8), documentation must be retained for at least 10 years after the last device has been placed on the market; for implantable devices the period is 15 years. For Class I single-use gloves the 10-year period runs from the last placing on the market of the batch.