The EU Machinery Regulation wants a *five-year trail* of safety changes

A log that lasts as long as a warranty

When you buy a machine, the warranty period is often two to five years. The EU Machinery Regulation asks for something similar: a log of safety-relevant software changes, kept for five years from when the machine was placed on the market ^[1]. Think of it like a service book for a car, but for the software that keeps a robot arm, a drone or an automated warehouse from hurting someone.

The Machinery Regulation, formally Regulation (EU) 2023/1230, replaces the old Machinery Directive and applies to machines placed on the market from 20 January 2027 ^[1]. It brings software to the front: safety-relevant software changes must be logged, machines must be protected against corruption, and machines with self-learning behaviour face special requirements ^[1].

For manufacturers, the question is not whether to keep logs. It is whether those logs will hold up when someone checks them five years later.

What the regulation says

The regulation does not spell out exactly how to log or protect the records. It says that safety-relevant software changes must be traceable for at least five years from the date the machine was placed on the market ^[1]. It also says machines must be protected against corruption ^[1], and machines with self-learning behaviour must meet additional requirements ^[1].

That leaves manufacturers to work out the details. The five-year clock starts when the machine reaches the market, not when it was built or when a change was made. A machine placed on the market in February 2027 must have a traceable log of its safety changes until at least February 2032.

Self-learning machines, separate rules

Machines that learn and adapt as they work get a section of their own. The regulation says machinery with self-learning behaviour must be designed so that safety is maintained even as the behaviour evolves ^[1]. That implies an ongoing record of what the machine has learned and how its behaviour has changed, not just a snapshot at the factory gate.

For a robot that adjusts its movements based on what it encounters on the shop floor, or a drone that learns to navigate around obstacles, that record is the only way to show later what the machine was doing at a given time.

Protection against corruption

Protection against corruption is mentioned but not defined in detail ^[1]. In practice, it means an attacker or an unauthorised insider should not be able to tamper with safety functions, logs or software undetected. Access controls and monitoring are the foundation, but they do not answer the harder question: if someone with the right access changes a log entry, how would you know?

That question matters when the log itself becomes evidence, for example during an investigation after an incident or in front of a notified body.

When logs become evidence

A log kept by the manufacturer is easy to question if the manufacturer is the one accused of a fault. Five years after a machine was placed on the market, the original engineer may have left, the development environment may have changed and the question will be: can you show that this log is exactly what was recorded at the time?

That is when the difference between a log and a provable log shows up. A log is a file you say you have not changed. A provable log is a record anyone you share it with can check, without having to trust you.

What this means for you

If you manufacture machines that will be placed on the EU market from 20 January 2027, here are the questions to ask now:

• Which software changes on your machines are safety-relevant, and how will you document them?
• Where and how will you store those logs for at least five years?
• If your machine learns or adapts, how will you record what it has learned and when?
• If a notified body, an investigator or a court asked you five years from now to prove a log entry has not been altered, what would you show them?
• Who in your organisation needs to understand these requirements, and have they seen the regulation?

The regulation gives manufacturers two years to prepare. The choices made in the next few months will shape what can be shown in 2032.

How a digital witness would work here

The thing to seal is each safety-relevant software change as it is logged: the version number, the change description, the date and the approval. The content stays in your systems; sealing takes only a fingerprint.

Sealing happens when the change is recorded, which means at the time the software is updated or the version is released. Anyone you share the log with later, such as a notified body, an insurer or a court, can calculate the fingerprint again and check that it matches the sealed one. If it does, the record has not changed. Change one character and it will not match.

A digital witness does not show that the change was safe, that the machine was compliant or that the log is complete. It shows that the record you are presenting is the one that was written at the time, unchanged since. The first 2,000 witnesses a month are free, and you can start with the REST API, the SDK or the MCP server at WitniumChain. Read the documentation to see how it fits your setup.

How it would work

1. When a safety-relevant software change is logged, your system sends a fingerprint of the log entry to WitniumChain and gets a witness ID back.
2. The log entry and the witness ID are stored together in your system.
3. When someone asks to see the log, you share the entry and the witness ID. They recalculate the fingerprint and check it matches.

What to watch

The regulation applies from 20 January 2027. Machines already on the market under the old Machinery Directive are not affected ^[1]. Guidance from notified bodies and industry groups on what counts as a safety-relevant change and how to document self-learning behaviour is expected over the next year.

For manufacturers, the time to decide how to keep five years of logs provable is before the first machine under the new regulation leaves the factory.