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# Lesson 3: The Four Layers

> Academy Foundations Module 1 Lesson 3: TBF-001, the four layers of a Digital Product Passport, who owns each layer, and why programmes that start at the technology layer stall.

**Module 1, Lesson 3 of 4. About 9 minutes.**

## Orientation

Once you know what a passport is, the next question is what a passport programme consists of, and
that is where organisations misallocate. Passport work spans legal interpretation, data ownership,
data collection and technical delivery. Those four things are owned by different people, move at
different speeds, and cost wildly different amounts. Teams that treat the work as one thing hand it
to whichever function is nearest, usually IT, and the result is a resolvable QR code sitting on top
of data nobody owns.

The four layer model exists to make that misallocation visible in the first week rather than the
ninth month.

The carrier, and none of the passport. Useful as proof that printing and scanning work, and
nothing more.

## Learning Objectives

A tieback framework that separates a passport into regulatory, governance, information and
technology layers, so a programme can see which layer it has actually built. Each layer answers a
different question, is owned by a different part of the organisation, and moves at a different
speed.

**Use it when** you are scoping a programme, allocating budget, or being told that a passport
project is nearly finished.

**Where it fails:** it is a lens for allocation, not a delivery methodology. It will not tell you
which attributes you need or what the deadline is, and it says nothing about sequencing inside a
layer. Do not turn it into a workstream chart with four equal boxes, because the layers are not
equal in effort.

## Reading the Layers

The canonical article sets out all four in detail. Read it with three questions in your hand: which
question does this layer answer, who in my organisation would own it, and how fast can it change.

The pattern that emerges is the useful part. The **regulatory** layer is not under your control and
is not yet complete. The **governance** layer produces no visible artefact, which is precisely why
it gets skipped, and it is the layer that determines whether the passport is still accurate two
years after launch. The **information** layer is where most of the real effort lives and is the
most durable investment, because governed data can be mapped to whichever field list eventually
lands. The **technology** layer is the fastest to build and the easiest to replace.

That last point has an uncomfortable corollary. The layer that produces the most visible progress
is the layer that matters least to the outcome. Progress reporting that measures the technology
layer will look healthy right up until someone asks where the material composition data came from.

#### [What is a Digital Product Passport?](/docs/knowledge-base/digital-product-passports/what-is-a-digital-product-passport)

Read the four layer section in full, including the four subsections and the practice note at the
end of it. The diagram there is the canonical rendering of TBF-001.

#### The Aurelia S2 across four layers

**Regulatory.** The trimmer, its battery pack and its textile strap do not sit under one regime.
Nobody in the company currently reads regulatory developments as part of their job. Owner: unfilled,
and that is the finding.

**Governance.** Composition data would come from the contract manufacturer, repair information from
after-sales, and conformity records from quality. No one decides who may publish or change an
attribute. Owner: unfilled.

**Information.** Roughly a third of the likely attributes exist in the product data system, another
third exist as PDFs in a shared drive, and the rest sit with suppliers who have never been asked.
Owner: product data management, in principle.

**Technology.** Identifiers, carriers and a resolver. Owner: IT, who could deliver it in a quarter.

The instinctive plan is to start where the owner exists and the work is understood, which is the
bottom layer. The correct plan starts by filling two owner gaps, which costs nothing and no capital
approval.

#### Assign owners for your own product

Draw the four layers for one product line and write a named person against each. Not a department:
a person.

Then mark each layer red, amber or green on one criterion only: would this person recognise the
responsibility if you told them today.

Most organisations produce green at technology, amber at information, and two reds. Those two reds
are your programme's actual critical path, and you found them in eight minutes without a budget.

## Knowledge Check

## Takeaways

* Four layers: regulatory (why it exists), governance (who is accountable), information (what it says), technology (how it is reached).
* Each layer has a different owner and a different speed.
* Governance is skipped most often because it produces no artefact, and it determines whether the passport stays accurate.
* The information layer carries most of the effort and most of the durable value.
* The technology layer is the fastest to build, the easiest to replace, and the worst progress measure.

**If you remember one thing:** scope from the top layer, spend on the third, and stop judging the
programme by the fourth.

## Sources

[What is a Digital Product Passport?](/docs/knowledge-base/digital-product-passports/what-is-a-digital-product-passport),
section The Four Layers of a Digital Product Passport, which is the canonical description of
TBF-001, plus Why Organisations Get DPP Projects Wrong.

## Related Docs

* [Lesson 4: From Carrier to Record, and What Is Still Undecided](/docs/academy/foundations/module-1/lesson-4)
* [Lesson 2: What a Passport Is Not](/docs/academy/foundations/module-1/lesson-2)
* [tieback Frameworks](/docs/knowledge-base/frameworks/overview)
* [What is a Digital Product Passport?](/docs/knowledge-base/digital-product-passports/what-is-a-digital-product-passport)