How to Merge Overlapping Taxonomies After an Acquisition

Two companies, two category trees, two ways of describing the same products. Here's how to merge them into one standard without a manual remapping project.

Two distributors merge. Each has a product catalog, a category structure, and years of institutional habit baked into both. Company A calls a category “Cable Management”; Company B splits the same products across “Cable Accessories” and “Containment Systems.” Neither is wrong. Neither maps cleanly onto the other. Someone now has to decide what the combined catalog’s taxonomy actually is, and manually remapping tens of thousands of products against a manually reconciled category tree is the kind of project that quietly takes a year.

Why this is harder than a simple mapping exercise

A taxonomy merge isn’t just relabeling — it’s reconciling two different ways of thinking about the same product space. Categories that look similar by name sometimes group products very differently. Categories with different names sometimes group products identically. A one-to-one mapping table built by eyeballing category names will get a meaningful fraction of products wrong, and those errors are invisible until a customer can’t find something they used to find easily under the old system.

This runs alongside the more familiar problem of migrating catalogs without creating duplicates — the same merger usually needs both: product-level identity resolution and category-level taxonomy reconciliation, at the same time.

A workable approach

Map at the product level first, category level second. Rather than trying to reconcile “Cable Management” with “Cable Accessories + Containment Systems” abstractly, look at what products actually sit in each category on both sides. The right category mapping falls out of comparing actual contents, not category names.

Decide on a target structure deliberately, rather than defaulting to whichever company’s taxonomy happens to be larger or more recently built. This is a good moment to consider adopting an external standard (ETIM, eCl@ss, or UNSPSC) as the merged target, rather than perpetuating either company’s internal one.

Reassign products to the new structure with confidence scoring, flagging ambiguous cases — products that genuinely don’t have a clean home in the merged taxonomy — for a person to place, rather than forcing an automatic best guess everywhere.

Preserve a mapping record from old category (both sides) to new category, so historical reporting can still be reconciled against the new structure rather than becoming meaningless the day the merge goes live.

What good looks like

Manual approach	Structured approach
Category-name mapping table, eyeballed	Product-content comparison drives the mapping
Full manual remapping of every product	Automated reassignment with confidence scoring
Historical reporting breaks at cutover	Old-to-new category mapping preserved

Working through a post-acquisition catalog merge? Book a 30-minute call.

Playbook

Migrating Catalogs Without Duplicates

Resolve product-level identity before a PIM migration or catalog consolidation.

Guide

Which Classification Standard Should You Use?

Choose whether ETIM, eCl@ss, UNSPSC, or an internal model should anchor your catalog.

FAQ

What's the hardest part of merging two companies' product taxonomies?

Categories with similar names often group products differently, and categories with different names sometimes group products identically, so mapping by category name alone produces meaningful errors. Comparing actual category contents at the product level is more reliable.

Should a merged catalog adopt one company's existing taxonomy or a new standard?

It is often worth considering an external standard such as ETIM, eCl@ss, or UNSPSC as the merge target rather than defaulting to either company’s internal taxonomy, especially if neither was built to scale cleanly.