Vice-chancellors accused funding chiefs of too much secrecy this week in debating a proposal to reward universities and colleges for attracting students from lower social classes.
The English Higher Education Funding Council has compiled university "affluence" profiles of students using home postcodes. It has sent profiles out to every institution. The council's interpretation of the postcode data is confidential.
The HEFCE board yesterday discussed using the data to widen access. One idea was that students from certain neighbourhoods attract a premium.
But universities in the prestigious Russell Group have decided to share their data and others may do likewise.
Peter Knight, vice-chancellor of the University of Central England, said he had collaborated with other vice-chancellors on an "I'll show you mine if you show me yours basis".
Diana Green, vice-chancellor of Sheffield Hallam University, was mystified by the secrecy saying the data could help monitor the effect of tuition fees. "What's wrong with universities in a particular region or city sharing the data?" she asked.
Colin Bell, vice-chancellor of Bradford University, said: "Institutions have got to prepare widening participation strategies and to do that they need detailed targets so that their achievements can be measured."
Leslie Wagner, vice-chancellor of Leeds Metropolitan University, said geodemographic data could be flawed and was a poor proxy for social class. He said: "I would be concerned if the data were used to provide incentives for those who were not doing so well at recruiting people from less well-off backgrounds."
Cliff Allen, of HEFCE's policy group said the methodology was the best available.