Product Relationship Types: SAME_AS, EQUIVALENT_TO, COMPATIBLE_WITH

SAME_AS is not EQUIVALENT_TO is not COMPATIBLE_WITH. In a distribution catalog, confusing them is the difference between a correct substitution and a returned order, so it is worth being precise about what each relationship claims.

A catalog’s value is not only in its products. It is in the relationships between them. Those relationships let a counter rep offer a substitute, a webshop cross-sell an accessory, a procurement system honour a supersession and an AI agent answer “what else works here?”. But a relationship is only useful if its meaning is exact. Below is the working vocabulary Claro uses, and the lines between the ones people most often blur.

The vocabulary

The three that get confused

These three carry the most operational risk because they look similar and mean very different things.

SAME_AS: the identical product, just different records. SKF 6204-2RS in Supplier A’s feed and 6204 2RS in Supplier B’s feed are SAME_AS. You can merge them into one identity and buy from whichever is cheaper, with no functional difference.

EQUIVALENT_TO: a different manufacturer’s product that is technically interchangeable for the application. SKF 6204-2RS and NSK 6204DDU are both sealed deep-groove bearings to the same ISO boundary dimensions (20 × 47 × 14 mm). They are EQUIVALENT_TO: usable as a substitute, but not the same product. Merging them would erase a real manufacturer distinction a customer may require.

COMPATIBLE_WITH: works together with another product, not in place of it. A 6204 bearing is COMPATIBLE_WITH a housing bored for 47 mm. Offering the housing as a substitute for the bearing because they are “related” is exactly the error this relationship exists to prevent.

Side-by-side

Close calls: variant, pack and replacement

• VARIANT_OF is not SAME_AS. ABB AF16-30-10-13 is a 100–250 V AC/DC coil version and AF16-30-10-11 a 24–60 V AC / 20–60 V DC coil version of the same AF16 family. Both are variants of the AF16 range; neither is the other. Only the coil code differs, which is why a one-digit difference must not be merged.
• PACK_OF changes the price maths. A box of 10 and a single unit share a GTIN family but not a price. Link them with PACK_OF and a quantity.
• REPLACED_BY is the manufacturer’s call. A successor part that supersedes a discontinued one is not the same as an equivalent from a competitor. Keep them apart.

Operational consequences

Each relationship drives a different action, which is why precision pays.

• SAME_AS: deduplication, price comparison, single source of truth.
• REPLACED_BY: automatic supersession so you do not quote a discontinued part.
• EQUIVALENT_TO: substitution offers and competitive cross-references.
• COMPATIBLE_WITH and ACCESSORY_OF: cross-sell and configuration (“you will also need…”).
• PACK_OF: correct unit-of-measure and price-per-unit maths.

Positive and negative edges

Relationships are not only assertions. They are also denials. A NOT_SAME_AS edge records a near-miss that must never be merged. Storing the rejection is how the catalog stops re-asking a question it has already answered. See product identity graph for how these edges persist.

Every relationship carries its evidence

In Claro, no edge is bare. Each SAME_AS, EQUIVALENT_TO or REPLACED_BY carries the source that justified it and a confidence score, so a substitution can be defended and a wrong one traced and corrected. That is the ontology and provenance working together, and it is the backbone of the Product Identity & Evidence Graph.

A rule of thumb for modelling

1. Start from the decision. What action will this edge trigger (merge, substitute, cross-sell, supersede)?
2. Choose the narrowest relationship that supports the action.
3. Require evidence proportional to the cost of being wrong: a substitution needs more than a cross-sell.
4. Record the near-misses.

Mapping editorial labels to the vocabulary

Teams often describe relationships in plain-language classes. These map onto the working vocabulary as follows. The left column is conceptual; the right column is what you store.

For the identity-level distinctions behind this mapping, see variant vs duplicate vs replacement. Worked examples: same MPN, different pack sizes (PACK_OF) and 6205-2RS vs 6205-2Z (NOT_SAME_AS, VARIANT_OF).

Directed and symmetric edges

EQUIVALENT_TO is the one to watch. Technical interchangeability is often one-directional, so the safe default is to store it as a directed edge from the candidate substitute to the part it can replace.

Evidence criteria per edge

A substitution needs stronger evidence than a cross-sell, and an unknown attribute counts against an EQUIVALENT_TO edge, not for it.

Directional and conditional substitutability

Suppose the successor part meets or exceeds every parameter of its predecessor. Then the successor can replace the predecessor. The reverse fails wherever the application uses the extra capability. A competitor part judged equivalent to the successor is not automatically a replacement for the predecessor either: the judgement was made against the successor’s specification, and the conditions that make it valid must travel with the edge.

Worked example (illustrative / synthetic)

Three invented parts: OLD-100 (Maker A, discontinued), NEW-100 (Maker A, its announced successor) and ALT-100 (Maker B). No real products are implied.

The graph is a chain with a one-directional meaning. The third edge is derived, not observed, so it should carry lower confidence and a flag showing it was inferred. Treat inferred substitution as a review item rather than an automatic offer.

Related

FAQ

What is the difference between SAME_AS and EQUIVALENT_TO? +

SAME_AS means two records describe the identical product, so they can be merged. EQUIVALENT_TO means a different manufacturer’s product is technically interchangeable for the application, so it can be offered as a substitute but must stay a separate product.

What does COMPATIBLE_WITH mean? +

COMPATIBLE_WITH means two products can be used together without one replacing the other, for example a bearing and a housing bored for it. It is used for cross-sell and configuration, never for substitution.

When should I use VARIANT_OF instead of SAME_AS? +

Use VARIANT_OF when two products are different configurations of the same family, such as two contactors that differ only in coil voltage. They share a parent but are not the same product, so they must not be merged.

What is a NOT_SAME_AS relationship for? +

It records a near-miss that must never be merged. Keeping it prevents a later run from merging the pair and prevents reviewers from re-investigating a question already answered.

Why do relationship types need evidence? +

Because each one triggers a different action, and a wrong substitution or supersession has a cost. A source and a confidence score let you defend the relationship, and trace and correct it if it is wrong.

Is a replacement the same as an equivalent? +

No. REPLACED_BY is the manufacturer’s own successor statement and applies to the same maker’s part. EQUIVALENT_TO is a technical interchangeability judgement across manufacturers. Keep them as separate edges because they have different sources and different risks.

Is substitution always two-way? +

No. A successor can cover everything its predecessor did and more, so it can replace the old part, while the old part cannot replace the successor wherever the extra capability is used. Store substitution as a directed edge with conditions, not as a symmetric one.

What evidence does an EQUIVALENT_TO edge need? +

A comparison of the identity-critical attributes for the product family from authoritative sources such as manufacturer datasheets, with each attribute recorded as agreeing, differing or unknown. Matching dimensions or similar descriptions alone is not enough.