What Is a Traceability Lot Code (TLC)?

A Traceability Lot Code is a unique alphanumeric descriptor used to identify a traceability lot within the records of the entity that assigned it. TLCs are the backbone of FSMA 204 -- they are the identifiers that follow food through the supply chain, enabling the FDA to rapidly trace contaminated products back to their source (Source: 21 CFR Part 1, Subpart S).

Every covered entity in the supply chain must record TLCs when they handle FTL food. Only certain entities are required to assign them.

When must a new TLC be assigned?

A new TLC must be assigned at exactly 3 points in the supply chain:

| Assignment Point | Who Assigns | What Happens | Regulatory Citation | |-----------------|-------------|--------------|---------------------| | Initial Packing | Entity that first packs a RAC (not from fishing vessel) | First TLC for produce enters the system | 21 CFR 1.1330 | | First Land-Based Receiving | First person on land taking possession from a fishing vessel | First TLC for seafood enters the system | 21 CFR 1.1335 | | Transformation | Entity that manufactures, processes, or changes food with FTL output | New TLC replaces input TLCs on transformed product | 21 CFR 1.1350 |

These are the only three events that create new TLCs. No other activity in the supply chain should generate a new TLC.

When must a TLC NOT change?

Existing TLCs must remain unchanged through all other supply chain activities:

• Shipping -- use the existing TLC
• Receiving -- use the existing TLC
• Holding or storing -- use the existing TLC
• Refrigerating or freezing -- use the existing TLC
• Simple temperature changes -- use the existing TLC

Changing a TLC during these activities would break the traceability chain and make FDA traceback impossible.

What format must TLCs use?

The FDA does not mandate a specific format for TLCs. Entities can use any alphanumeric system that uniquely identifies a traceability lot within their records.

GS1 best practice (recommended)

The industry-recommended approach from GS1 US and the Produce Traceability Initiative (PTI):

• GTIN (GS1 AI-01) + Batch/Lot Number (GS1 AI-10) = unique TLC
• Encoded in a GS1-128 barcode on the case label
• Provides a globally unique identifier that works across supply chain partners

Other acceptable formats

• Internal lot numbers (if unique within the assigning entity)
• Date-based codes (if unique)
• Sequential numbering systems
• Any system that uniquely identifies a traceability lot within your records

The only requirement is uniqueness within your own records. Two different lots of food cannot share the same TLC within the same entity.

What is a TLC source?

The TLC source is the physical location where a TLC was assigned. It tells anyone in the supply chain where the TLC originated:

| Assignment Event | TLC Source Is | |-----------------|---------------| | Initial Packing | The packing location | | First Land-Based Receiving | The receiver's location | | Transformation | The transformation location |

The TLC source must be included in Shipping and Receiving CTE records so the FDA can trace any TLC back to where it was created.

What is a TLC source reference?

A TLC source reference is an alternative way to provide the FDA access to the TLC source location description. Instead of repeating the full address in every record, entities can reference it using:

• FDA Food Facility Registration Number
• GS1 Global Location Number (GLN)
• A web address pointing to the location information

This simplifies recordkeeping for entities handling high volumes of TLCs from multiple sources.

How do TLCs propagate through the supply chain?

TLCs follow food from assignment to consumer. Here is a typical flow:

INITIAL PACKER assigns TLC "LOT-A-001"
  --> TLC "LOT-A-001" shipped to DISTRIBUTOR
    --> DISTRIBUTOR records TLC "LOT-A-001" on receiving
    --> DISTRIBUTOR ships TLC "LOT-A-001" to RESTAURANT
      --> RESTAURANT records TLC "LOT-A-001" on receiving
      --> Restaurant cooks and serves food -- no new TLC needed

When transformation occurs, the TLC changes:

INITIAL PACKER assigns TLC "LOT-B-002"
  --> TLC "LOT-B-002" shipped to PROCESSOR
    --> PROCESSOR receives TLC "LOT-B-002"
    --> PROCESSOR transforms food --> assigns NEW TLC "MIX-C-003"
      --> Links input TLC "LOT-B-002" to output TLC "MIX-C-003"
    --> PROCESSOR ships TLC "MIX-C-003" to DISTRIBUTOR
      --> TLC "MIX-C-003" continues through the chain

The FDA can follow TLC "MIX-C-003" back to the transformation record, find input TLC "LOT-B-002," and trace that back to the initial packer and farm.

What do restaurants need to know about TLCs?

Restaurants have the simplest TLC obligations:

1. Receive food with a TLC already assigned by an upstream packer, receiver, or transformer
2. Record that TLC in their Receiving CTE documentation
3. Do NOT assign a new TLC -- restaurants are exempt from TLC assignment
4. Do NOT change existing TLCs

The TLC will appear on delivery invoices, case labels, or packing slips. The practical challenge is ensuring delivery documents include TLCs and that receiving staff capture them.

Exception for non-regulated sources: If a restaurant receives FTL food from a supplier that does not provide a TLC (for example, a farm below the $250,000 threshold), the restaurant is not required to assign one themselves (Source: 21 CFR 1.1345(b)). Record as much information as possible and note the absence.

How long must TLC records be kept?

All records containing TLCs must be retained for 2 years (24 months) from the date created (Source: 21 CFR 1.1455). Records must be available to the FDA within 24 hours of a request.

Because TLCs are the thread connecting every CTE record across the supply chain, maintaining accurate and retrievable TLC records is the foundation of FSMA 204 compliance.