As a registrant, you are responsible for registering the nanoforms you manufacture or import. Your registration must contain characteristics and a specific hazard dataset for each nanoform or set of nanoforms. 

In principle, you must characterise each nanoform of a substance individually. However, you can also identify sets of nanoforms if they clearly define the boundaries of the set and justify that the hazard, exposure and risk assessments can be performed jointly for all the nanoforms in the set. In this case, the information you submit for that set of nanoforms under Annexes VII-X will be deemed representative for all the nanoforms covered by the set.

The general information required by Annex VI, including the characterisation of nanoforms or sets of nanoforms, must be submitted separately by each registrant.

Co-registrants can choose to submit information required in Annexes VII-X either separately in their own dossiers or they can rely on the lead registrant to submit this information jointly. With either approach, the link between each nanoform or set of nanoforms and the corresponding set of data from Annexes VII-X must be clearly indicated in the dossier. 

When a registration dossier covers nanoforms, the completeness check verifies that:

• a complete characterisation is provided for each nanoform or set of nanoforms;
• each set of nanoforms has a complete justification that the hazard, exposure and risk assessments can be performed jointly;
• each nanoform or set of nanoforms is linked to a specific and complete dataset of Annex VII-X information; and
• when information requirements are waived based on Column 2 of the relevant REACH annex, any provisions specific to nanoforms are followed, as applicable.

The hazard information on the nanoforms may be submitted by the lead registrant at a later stage.

When checking co-registrants’ dossiers, ECHA does not verify the completeness of the corresponding hazard information submitted under Annexes VII-X. Therefore, it is crucial for members that rely on jointly submitted data to provide a link to the relevant boundary composition in the lead dossier. ECHA reserves the right to assess the completeness of the co-registrant’s dossier at a later stage in relation to the information submitted jointly by the lead registrant under Annex VII-X.