Why the same supplier shows up three times in your ERP

The conversation always starts the same way. Someone pulls a purchasing report, sees "TRANSPORTADORA SAO PAULO LTDA", "Transp. São Paulo" and "TRANSPORTES SP LTDA - ME" and concludes that the master data team is careless.

It is almost never that. Duplication in suppliers is a symptom, and the diagnosis has three probable causes.

Cause 1: there is no required key field

If the system lets you save a supplier without a CNPJ (Brazil's company registration number), duplication is inevitable. Without a key, the system has no way of knowing that two records are the same company, and the operator holding an invoice with a short deadline will create it again.

The test is simple: try to create a supplier without a CNPJ. If the system lets you, you have found the cause.

There is one legitimate case: the foreign supplier, who has no CNPJ. There the solution is not to free up the field for everyone, it is to have an explicit alternative key for that type, with a different approval.

Cause 2: there is no approval flow

Creating a master record is not a typing operation, it is a decision. When any user can create a supplier directly, every emergency generates a new record.

The minimum flow that works has three steps: a request with justification, a duplicate check by someone who knows the domain, and a recorded approval. None of them needs a very expensive tool; they need a named responsibility.

The gain is not just avoiding the duplicate. It is having, months later, a record of who asked and why.

Cause 3: there is no domain owner

This is the one that costs the most. Without someone formally responsible for the "supplier" domain, nobody decides the naming standard, nobody arbitrates when two areas disagree and nobody answers when the base degrades.

The domain owner is not the person who types. It is the person with the authority to say "this is the standard" and to hold back a record that doesn't follow the standard, even when the rush comes from the director.

What to do with the duplicates that already exist

Don't start with the cleanup. Start by closing the door: a required key field and an approval flow. Cleaning without closing the door is bailing water with a bucket, and the rework demoralizes the whole initiative.

With the door closed, handle the backlog by relevance, not by volume. Suppliers with financial activity in the last year first; a supplier inactive for five years can simply be blocked.

When merging records, keep the trail. Someone will ask, in a lawsuit or an audit, where the old record went. Overwriting without history swaps a quality problem for a compliance problem.