Digital Object Identifiers (DOIs) are persistent links to digital objects. The University of Cambridge holds a licence to assign DOIs to selected scholarly research outputs ("Research Outputs") deposited into the University of Cambridge research repository "Apollo" ("Repository"). All DOIs assigned by the University of Cambridge need to be registered, and be compliant with the requirements of the DataCite organisation.

What types of Research Outputs can get a DOI?

The University of Cambridge will assign DOIs with the Cambridge prefix (CAM) to selected Research Outputs, including datasets, theses and working papers. For Research Outputs which already have DOIs, we will not assign a Cambridge DOI to the record.

Modifications to Research Outputs

Modifications to Research Outputs once a DOI has been assigned are allowed. In cases where such modifications involve changing one or more files associated with the record, this will result in a new version being created, and a versioned DOI will be assigned. When changes only involve modifications of the metadata associated with a record, these can be performed on the same version, following DataCite best practice guide (

The only exception where modifications to Research Outputs are not permitted is for research theses: modifications to the record will only be accepted until the final version of the thesis is deposited in the repository.

Take down policy

Content held in the Repository is intended for long-term preservation; however, in some cases items may be withdrawn. Reasons for withdrawal might include, for example:

  • Proven copyright violation or plagiarism
  • Legal requirements
  • National security
  • Falsified research
  • Ethical requirements

Withdrawn items will retain the DOI, and the withdrawal notice will be indicated on the landing page of the Research record in the Repository, but the Research Output itself will not be accessible. More information related to the takedown policy is available from the related policies link.

We reserve the right to act with discretion in cases not covered by this policy, or where circumstances require additional flexibility.

Revision history
Policy version:3
Date of last policy review:November 2023
Name of reviewer:Agustina Martinez-Garcia
Original policy creation date:2016/11/09
Name of creator:Marta Teperek and Danny Kingsley
Date for next review:November 2023
Frequency of reviews:At least annually
Review is the responsibility of:Head of Open Research Systems
Location of policy:
Related policies:Repository terms of use