Queen’s University Belfast holds an extensive database on tree rings, particularly Irish oaks; information that may be used in the reconstruction of past climate conditions. A request for this information under the United Kingdom’s new Freedom of Information legislation was disputed on the basis of intellectual property rights, compliance costs and the usefulness of the information as a proxy for temperature. Costs of compliance were exaggerated by the university, and there was a reluctance to classify information as environmental in order to avoid disclosure. Arguably, copyright subsists in the requested datasets but this, in itself, would not prevent disclosure. The validity of the tree ring data as a proxy for past temperatures would only become a relevant legal consideration under the public interest test for disclosure of ancillary information held by Queen’s University Belfast in non-electronic format. However, scientific uncertainties emerge from the analysis under public interest, potentially raising issues for the United Nations’ International Panel on Climate Change that has incorporated this data into its influential 2007 assessment report.