OpenBOM Reference-Instance Model

OpenBOM (
Apr 1 · 3 min read

Many users and customers are asking me to provide more explanations of the fundamental model OpenBOM is using for data management in BOM. I’m working on some additional materials for our online help and decided to share some of the initial notes in the blog. Also, to help you ask more questions.

There are two main elements that were driving our decisions about OpenBOM models.

  1. Flexible and simple;
  2. Universal to model any product data.

In terms of flexibility and simplicity, OpenBOM model is designed to be real-time and instance level accessible. It means, I can define a BOM and modify definitions of properties on the fly. This is important since it makes it very similar to so much loved Excel and spreadsheet. At the same time, it is structured since this data can be reused.

From product data modeling standpoint, OpenBOM gives you a way to create Reference-Instance Model, which I’d like to explain below.

A reference is an abstract object that can be modeled in OpenBOM. This object has a set of properties and represents any part, assembly, or component (terms are sometimes different in different companies). I prefer standard and engineering parts. However, if you have a better name, please let me know.

So, reference can be a nut, a bot, a screw, an electric motor, or any piece of equipment you buy, manufacture, or outsource. OpenBOM is using catalogs to define references and configure data properties.

An instance is an actual part used in a specific product (engineering product or built product) or an entire product you build. So, if you create a skateboard, which has 4 wheels, then you have 1 reference of a wheel and 4 instances of a wheel.

A picture below shows how data is managed in OpenBOM to support Reference-Instance Model.

As you can see on the picture, references are represented as nodes, while instances are represented as links. You can define any product data using this model.


OpenBOM created Reference-Instance Model, which is flexible, yet simple to manage data about products, components, and related information. This model is in development to support more sophisticated products, and we will be introducing new elements of the OpenBOM model later this year.

Meantime, if you have questions, I’ll be happy to talk.

Best, Oleg

P.S. Let’s get to know each other better. If you live in the Greater Boston area, I invite you for a coffee together (coffee is on me). If not nearby, let’s have a virtual coffee session — I will figure out how to send you a real coffee.

Want to learn more about PLM? Check out my Beyond PLM blog and PLM Book website.

OpenBOM (

Written by

Online tool to manage you Bill of Materials and Part Catalogs. Real-time collaboration for teams and supplier, sync data with CAD, PLM, ERP. More -

Welcome to a place where words matter. On Medium, smart voices and original ideas take center stage - with no ads in sight. Watch
Follow all the topics you care about, and we’ll deliver the best stories for you to your homepage and inbox. Explore
Get unlimited access to the best stories on Medium — and support writers while you’re at it. Just $5/month. Upgrade