From a description of a stream to an introduction between two companies.

1. Describe what you have, or what you need

Registration asks for the basics only: your name, a company e-mail address, your company and the country it is registered in. GreCoM checks the company against the Dutch trade register; until that check has passed, no identity can be exchanged with anyone.

You then describe a residual stream, or a material requirement, through a step-by-step form that saves as a draft at every step. A producer states the residual category and material category, the physical state, quantity and period, availability, location, the legal status of the material and whether it is hazardous. A buyer states the material category or a target element, which physical states are acceptable, the quantity and period needed, and a minimum and maximum for each property that matters — marking each one mandatory or not.

The technical part is structured rather than free text: elements and their concentrations, and four measured properties — moisture content, pH, particle size and purity — each with the method and the date of measurement. That is what makes a comparison possible at all.

2. A reviewer reads it before it goes live

Nothing you enter is matched against anything until a GreCoM reviewer has read it against a checklist: relevance, completeness, the declared legal status, technical plausibility, the quality of the evidence, contamination, availability, geography, and the risk that the anonymised card could identify you. The target is three working days. For the first fifty entries on the platform, a second named reviewer signs off as well.

A reviewer can also ask you for more information rather than approving or rejecting, and a value that GreCoM has transcribed from a document of yours does not count as your data until you have confirmed it.

An entry that has been through this is marked Data reviewed. Not verified, and not certified.

3. The engine narrows, and says why

Once live, every stream is compared with every requirement. The engine rejects a pair outright on four grounds:

• the material category is not an exact match;
• the residual’s physical state is not one the buyer said they accept;
• the producer’s quantity is below half the buyer’s stated minimum;
• any property the buyer marked mandatory is outside the range they gave.

What survives is a candidate. It carries a finding per dimension — material, element, technical properties, quantity, availability, geography, application — and, for the reviewer, the exact distance between what was asked for and what was stated. A candidate is not visible to either company.

The four rules, and the thresholds inside them, are settings rather than assumptions buried in the software. They are changed deliberately and in one place, and every match records which version of them decided it — so a decision can still be explained a year later.

4. A person decides — and there is no score

A named reviewer reads each candidate and does one of three things: publishes it, holds it for more information, or does not publish it with a recorded reason. On publication they write the assessment that both companies read.

5. The anonymised card

When a match is published, each side sees a card describing the other. It carries the sector, a coarse region — North, East, South or West — a quantity band rather than a figure, the material category and the intended application, up to three key properties as bands rather than measured values, a flag if the stream is declared hazardous and a flag if processing may be required.

Before a card is published, a reviewer checks that enough other companies share its profile that it does not describe one identifiable company. Where it does not, the reviewer widens a band or records in writing why the card is safe to publish; either way the check and the number it was checked against go onto the record. What is visible, and to whom.

6. Disclosure, in one step

Either side may express interest. When both have, either may request that identities be disclosed. GreCoM reviews the request — target two working days — and on approval both identities are released at the same moment. There is no state in which one company knows the other and is not known in return; a fault at that moment leaves neither written.

A request nobody answers expires after fourteen days and the match returns to where it was. An expressed interest can be withdrawn. Documents GreCoM has cleared become visible at the same point, never before.

The buyer sees the card. Nothing else leaves the producer.

Both express interest. Neither knows who the other is.

Either may request disclosure. GreCoM checks the request before anything is released.

Both identities are released in a single step — both, or neither. From here it is between the two companies.

Step 1 Step 2 Step 3 Step 4

7. Afterwards, and staying current

From the introduction on, the conversation is between the two companies. GreCoM is not a party to it, does not price it, and does not take possession of anything.

A producer confirms every quarter that a stream is still available. A stream that is not confirmed is paused — withdrawn from matching — and after a second consecutive missed confirmation it is archived. The record is kept; the supply is not presented as live when nobody has said it is.

The words GreCoM uses

The vocabulary is deliberate, and the build refuses to ship the alternatives:

• Company checked — the company was found in the trade register.
• Data reviewed — a reviewer read the entry against the checklist.
• Match assessed — a reviewer decided this pairing and wrote what both sides read.
• Residual stream — not a category of disposal, and not the legal term, which is a separate field a producer declares.

What you will not find: verified, validated, certified, guaranteed, or a percentage attached to a pairing. GreCoM has not tested your material and does not claim to have.