Ministers have been strongly criticised for including a valuable database containing 29 million postal addresses in the sale of the Royal Mail to boost the share price.
The Commons Public Administration Committee said the Postcode Address File (PAF) should have been retained as a "national asset" freely available to all for the widest benefit of the economy.
It said the PAF's disposal to the private sector for "short-term gain" in last year's Royal Mail flotation was an "unacceptable and unnecessary consequence of privatisation" which could hold back economic innovation and growth.
Committee chairman Bernard Jenkin said: "The sale of the PAF with the Royal Mail was a mistake. Public access to public sector data must never be sold or given away again."
Names of individuals are not included in the database except when the building name or number or unavailable.