Quick answer
A mixed-date-code offer is not automatically unacceptable, and matching date codes do not by themselves prove a single manufacturing lot. Evaluate the exact part number, the identity and quantity of each offered group, its documentation, handling history and your application’s acceptance requirements. Record the decision before the supplier combines material or ships it.
For obsolete components, a buyer may need several small quantities to complete one order. The risk is not simply that two dates appear on the quotation. The practical problem is losing the connection between the delivered pieces, their labels and the evidence used to accept them.
1. Separate date codes, lot identity and delivery arrangements
Use precise language in the enquiry. A date-code restriction, a requirement for one traceable lot and a request for one shipment are three different conditions.
| Term | What to clarify |
|---|---|
| Date-code restriction | The manufacturer’s code format, permitted range and any customer-specific limit. |
| Single-lot requirement | Which manufacturer lot or trace identifier defines the group, and what documents link it to the offered quantity. |
| Multiple offered lots | The quantity, labels, documentation and acceptance status of every separately identified group. |
| Split shipment | The delivery schedule and which accepted groups are included in each dispatch. |
A split shipment can contain material from one identified lot. One delivery can contain several lots. Avoid using “same shipment,” “same date” and “same lot” interchangeably in purchase-order notes.
2. What manufacturer documents actually establish
Manufacturer-controlled mixed packing can exist
TI’s General Quality Guidelines, Rev. Q dated April 15, 2025, describes its own lot-combination policy: at final packing, an intermediate bag, box or reel may contain up to four date codes no more than 52 weeks apart. The same document describes lot/batch identification and container tracking. [1]
This is a manufacturer-specific policy, not permission for an independent supplier to pool unrelated stock. It does not approve a particular secondary-market offer or override a customer’s single-lot requirement. The procurement inference is narrower: multiple date codes alone are insufficient grounds for deciding authenticity or acceptability.
Keep the original trace identifiers with the material
TI’s product-marking and label guide distinguishes package markings from label information and identifies the Ship Trace Code, or STC, as a unique code for a box, reel or bag. It recommends that data for product-genealogy traceability. [2]
For a buyer, the practical action is to request legible original-label photographs and preserve their connection to the offered pieces. Do not assume that a copied label, a seller’s inventory number or a familiar-looking top mark independently verifies origin. Where evidence is missing, describe the gap instead of replacing it with a guessed code.
A sealed date is not a manufacturing date
NXP’s notification 202011011I announced an additional sealed-date field for the applicable moisture-barrier-bag labels from January 2021. That notice concerns a packaging-label field, not a new identity for the product. [3]
The lesson is to ask what each displayed date means. Do not substitute a bag-sealing date, seller receipt date or inspection date for the manufacturer’s production information. Manufacturer and product-family conventions must be checked individually.
3. Request a lot-by-lot offer, not just a total quantity
Ask the supplier to break the quotation into identifiable groups. A useful offer states:
- The full manufacturer ordering code, including all relevant suffixes.
- The quantity available in each group and the identifier used to keep it separate.
- The observed markings, original label details and date-code information, with uncertainties identified.
- The stated condition, packing format and any disclosed repacking or handling history.
- The documents available for that group and the scope of any inspection or testing already performed.
- The proposed checks, acceptance conditions and shipment allocation.
These are suggested purchasing fields, not a claim that every supplier can provide every record. Missing original documentation should remain visible in the offer so the responsible engineering or quality team can assess it.
For example, the CD54HCT175F3A and LM111JG catalogue pages identify exact devices. Neither a catalogue page nor this article establishes how many lots are currently available or what traceability accompanies an eventual quotation. Confirm those details for the material actually offered.
4. Compare the options without losing the group boundaries
Illustrative example only—not ZZX inventory: a customer needs 120 pieces of one approved part number. Offer A describes 120 pieces in one identified group. Offer B describes 80 pieces in Group A and 40 in Group B.
The totals match, but the evaluation is not finished. Compare the supporting records and acceptance route for each group. If only Group A has been inspected, do not describe all 120 pieces in Offer B as inspected. If Group B has an unresolved condition or identity question, agreeing to buy Group A does not resolve it.
Keep the two groups separately identified through receiving and disposition. If your process requires an internal reference, link it to the available original identifiers rather than presenting a new internal number as a manufacturer lot code.
For a strict single-lot requirement, ask for an offer that meets the defined requirement or escalate the proposed exception for approval. Do not silently relax it to “same date code” because that wording is easier to satisfy.
5. Agree inspection scope and acceptance before purchase
The responsible quality or engineering team should determine the checks needed for the application and the offered material. Record whether an activity covers every piece, selected samples or only particular groups. Define how findings will be reported and what happens to any unresolved group.
Do not automatically apply one group’s results to another. Equally, do not assume that every difference requires the same test programme. The acceptance route should reflect the actual evidence and risk; this article does not prescribe a universal sample size or certify a test method.
Use our documentation and traceability guide to distinguish the records involved. For questions about storage and older material, see the date-code and storage guide. Neither a recent date nor a matching set of labels replaces the agreed acceptance checks.
6. Put the agreed boundaries in the RFQ
“Please quote the exact manufacturer ordering code below and identify each offered lot or separately controlled group, its quantity, date-code information, condition and available documentation. State whether the offer contains multiple lots or date codes. Keep the groups identifiable and obtain our written approval before combining or substituting material. Report inspection and test scope by group and confirm the agreed shipment allocation.”
If one manufacturer’s lot is mandatory, state that requirement explicitly and define the supporting evidence required. Add any customer-specific restrictions and the delivery schedule. The RFQ checklist covers the remaining purchasing fields.
Frequently asked questions
Are mixed date codes proof of counterfeit components?
No. They are a reason to understand the offer and its evidence, not a stand-alone authenticity verdict. Manufacturer packing policies, material history and customer requirements matter.
Do identical date codes guarantee one lot?
No. Establish the relevant lot or trace identity and its link to the offered quantity. A matching date field alone is not that evidence.
Does one delivery mean one manufacturing lot?
No. Delivery arrangements and lot identity are separate. Ask for the actual group breakdown.
Can a supplier combine groups after inspection?
Agree the handling and identification requirements before purchase. Any proposed combination must preserve the evidence needed for acceptance and follow the customer’s approval requirements.
Request an offer with clear lot information
Send ZZX Electronics the full ordering code, quantity, required delivery and any single-lot or date-code restriction. Ask for confirmation of the currently offered material, available documents and any proposed inspection scope in the written quotation. This article does not promise original traceability, reserved quantities or manufacturer authorization for a particular lot.
Contact ZZX Electronics with your requirements before agreeing to a mixed-lot purchase.
Sources and technical references
- [1] Texas Instruments General Quality Guidelines, Rev. Q, April 15, 2025 — sections 25–29 on identification, packing, date codes and lot combination.
- [2] TI Product Markings and Labels — manufacturer guide to markings, labels and Ship Trace Codes.
- [3] NXP notification 202011011I: NXP Will Add a Sealed Date to the Product Label — historical notification on an additional label field for applicable packaging.
Sources and catalogue links checked October 19, 2026. General purchasing steps and the numerical example are editorial recommendations, not a manufacturer approval, test certificate or universal acceptance standard. Follow the exact product documentation and customer-approved requirements. Images are AI-generated editorial illustrations, not actual ZZX inventory, lot labels, facilities or inspection results.
