Why a QP Can Refuse Your Batch: Annex 16 in Plain Terms

A batch arrives with a certificate of analysis showing every result within specification, and it is refused. From a supplier's side this looks arbitrary, or political, or like a customer inventing a reason to delay payment. It is none of those. It is one person declining to sign a statement they would be personally accountable for.

That accountability is the whole mechanism, and it explains most of what suppliers find puzzling about European batch release.

What certification actually is

Certification is a declaration by a named individual that a batch has been manufactured and checked in accordance with the applicable requirements, and that the batch is suitable for release. The declaration is personal. It is not a company position issued by a committee, and it cannot be delegated to a form.

Because it is personal, the QP's question is not "does this batch meet specification". It is "has a system I trust already established that, and can I see the evidence". Those are different questions, and a specification-compliant batch can fail the second one.

Six reasons a technically compliant batch gets held

One: the documentation set is incomplete in a specific way

Not missing in bulk, which is easy to catch, but missing at the seam: a batch record page without a second signature, an analytical report referenced but absent, a re-test whose result appears without the original failing result next to it.

Seam gaps are the hardest to see from the supplier's side because every document exists. What does not exist is the trail connecting them.

Two: the certificate of analysis contradicts itself

A result at the limit with no comment, an assay reported on a basis that differs from the specification's basis, a total impurity figure that does not equal the sum of the named ones, a method named in the header that differs from the method in the body.

Each of these is a small internal inconsistency and each one is a reason to pause. Our note on COA internal consistency sets out the checks that catch them before shipment.

Three: the investigation is open

An out-of-specification result that was investigated and closed is a finished event. The same result with the investigation still open is a batch whose status is unknown, regardless of the re-test result.

A QP cannot certify a batch whose quality status is unresolved, and an open investigation means exactly that. Suppliers who ship while an investigation is open are shipping a decision to somebody else.

Four: the transport conditions cannot be reconstructed

Temperature excursions, unplanned transhipment, a missing data logger or a logger with a flat battery all produce the same outcome: the batch's condition during transit is unknown. For a substance with a defined storage condition, unknown is not acceptable.

The fix is cheap and rarely implemented: a logger whose data travels with the shipment and is readable at arrival. See shipment document consistency.

Five: the supplier is not on the approved list, or the site is not

Approval is per site, not per company. A supplier who has been approved for one plant and ships from another has shipped from an unapproved site, and no amount of certificate-of-analysis quality changes that.

Six: a change happened and was not notified

A new solvent, a different supplier of a starting material, a modified drying step, a new packaging liner. Each is a change to something the customer's file may reference, and the notification obligation belongs to the supplier.

The commercial damage here is disproportionate. A notified change is a conversation. An unnotified change discovered at release is a credibility event that outlasts the batch.

Reason	Document that exposes it	What prevents it
Seam gaps in documentation	Batch record and analytical report set	Release checklist signed before dispatch
Contradictory COA	Certificate of analysis	Consistency check against the specification
Open investigation	Deviation and OOS log	Status declared on the shipping documents
Transport conditions unknown	Logger data and transport record	Logger in every shipment, data at arrival
Unapproved site	Approved supplier list	Confirm approval before booking freight
Unnotified change	Change control record	Notification clause with a defined window

What the QP is not doing

Three misconceptions cost suppliers the most time.

They are not re-testing. Certification relies on the producing site's control system and, where applicable, on import testing. A QP who distrusts the system does not compensate by testing more; they decline.

They are not judging your commercial behaviour. Late delivery or a pricing dispute does not enter the decision. When a batch is held, the reason is almost always documentary and almost always stated.

They are not able to make an exception. The personal nature of the declaration is what makes it strong, and it is also why pleading produces nothing. The route forward is always the same: close the gap and resubmit.

How suppliers reduce the exposure

Most refusals are preventable before the drum is closed. Four practices do most of the work.

1. Run the release checklist against the customer's own requirements, not against your standard pack.
2. Ship with the investigation status visible, so an open item is disclosed rather than discovered.
3. Include transport data as part of the shipment, not on request.
4. Notify changes before they take effect, with the affected batches identified.

For how the internal signature chain feeds the QP's decision, see batch release signature chain. For the notification obligation itself, see change notification and supply.

Primary sources: EudraLex Volume 4, Annex 16 for certification by a qualified person, the EMA GMP overview for the underlying obligations, and PIC/S for the inspection guidance that national authorities apply.

Frequently asked questions

Can a QP refuse a batch that meets specification?

Yes. Certification is a declaration that a system has established the batch's compliance. If the evidence trail has gaps, an open investigation or an unapproved site, a specification-compliant batch can still fail that test.

Does the QP rely on the supplier's testing?

Largely yes, together with any import testing required in the destination market. Certification is not a re-analysis; it is a judgement about whether the control system can be relied on for this batch.

What happens to a refused batch?

It stays un-released. The gap is closed, the evidence resubmitted, and the decision taken again. Material is not destroyed for a documentary reason, but it cannot move until the reason is resolved.

Is import testing always required in the EU?

The requirements depend on the market, the material and the arrangements in place, and they change. What does not change is that a QP needs a basis for the declaration, and import testing is one way of providing it.

Does a change of packaging need to be notified?

It can, because packaging is part of what was assessed and what the customer's file may describe. The safe rule is to notify anything that appears in a specification or a certificate, and let the customer decide the significance.

Can a supplier appeal a QP decision?

There is nothing to appeal in the usual sense, because the decision is personal and evidence-based. The effective response is to close the specific gap identified and resubmit, which usually resolves the matter faster than escalation.