Pyner
Blog
←Back to blog
Workflow/February 27, 2026/6 min

How to import a CSV for merger analysis without wasting time on cleanup

CSV is often the fastest source format and the least stable one. This guide shows how to prepare, map and normalise imports so they accelerate the analysis instead of slowing it down.

Author

Pyner Team

Published

February 27, 2026

Updated

March 9, 2026

Key takeaways

  • A clean CSV import starts with explicit mapping of critical columns.
  • Banner, role and address inconsistencies should be resolved before running concentration analysis.
  • Traceability of corrections is just as important as the cleanup itself.

Short answer

A strong CSV import for merger analysis relies on explicit mapping, cleaned source data and visible correction logic. That preparation is what makes the downstream calculations more reliable and easier to defend.

Why CSV imports often go wrong

CSV feels simple because it is universal. In reality, it carries all the common ambiguities: poor column naming, incomplete addresses, inconsistent banner formats, duplicates and missing values.

If those issues are ignored early on, they contaminate the full analysis. The time saved at the start is then lost in manual corrections, cross-checks and recalculations.

Map the right columns from the start

A strong import starts with explicit mapping. You need to know which columns identify the outlet, the banner, the address, the role in the transaction and the metric used for calculation.

This should not be seen as a purely technical form step. It is a quality-control stage: if the mapping is clear, downstream calculations become far more reliable.

  • separate business identifiers from display fields
  • plan for banner and group resolution
  • validate critical columns before running calculations

Normalise without overengineering

The goal is not to build a full data-engineering pipeline. The goal is to obtain a coherent dataset for a fast and accurate concentration analysis.

The best approach is to correct the inconsistencies that matter most: banners, roles, addresses and core metrics. Beyond that, sophistication should remain proportionate to the case.

Preserve the cleanup trail

Every material correction should remain visible or recoverable: banner grouping, outlet exclusion, role reassignment or store-format reclassification. Without that traceability, the import becomes a black box.

A strong workflow leaves a clean record of what was changed. That is what makes the analysis reproducible, easier to explain to clients and less exposed to silent errors.

Useful resources

CSV import documentation↗Column mapping guide↗Brand groups↗

Frequently asked questions

Which columns matter most in a merger-analysis CSV?

The most sensitive fields are usually banners, addresses, party roles and the core calculation metric, because they directly affect the outputs.

Why does cleanup traceability matter?

Because the file may evolve and be reviewed. If material corrections are invisible, it becomes much harder to explain or rerun the analysis later.

Can a better CSV import really improve legal analysis?

Yes. Cleaner data reduces silent errors, speeds up recalculations and makes methodological choices far easier to defend.

Ops

Make CSV import an accelerator instead of a bottleneck

The Pyner import wizard helps teams map, clean and exploit data without multiplying intermediate spreadsheets.

Explore Pyner

Read next

Pillar guide

Retail merger control: a practical guide to local market analysis before filing

Relevant market

Defining a local relevant market in retail without drifting into pure theory

Read next

Pillar/Pillar guide

Retail merger control: a practical guide to local market analysis before filing

This pillar guide brings together the foundations that matter in retail merger control: relevant market definition, local market shares, HHI, catchment areas, prioritisation of sensitive zones and preparation of filing-ready deliverables.

merger controlretaillocal marketfiling
March 16, 202612 min
Strategy/Relevant market

Defining a local relevant market in retail without drifting into pure theory

In retail merger cases, the debate is never only about numbers. It is also about the right market definition. This guide explains how to build a local market that is more credible, readable and operational.

relevant marketretaildistribution
March 14, 20269 min

Launch your first analysis now

Contact us for a personalized demo of the platform.

Free trialRequest a demo
Pyner

Product

FeaturesPricingCSV ImportInteractive mapPDF ReportAPI

Resources

DocumentationMethodologyBlogUse casesFAQChangelog

Company

AboutContactPartnersCareers

Legal

TermsPrivacyCookiesLegal notice

© Pyner | Paris, France

ADLC Compliant · EU Commission · CMA