Almost 200 Caerphilly County Borough Council employees signed confidentiality agreements upon leaving the authority over the past five years, according to a Freedom of Information request.
The council said the reasons for the clauses included the protection of commercially sensitive and financial information, and insisted it does not use so-called gagging clauses.
The information was obtained after a Freedom of Information request from the Plaid Cymru council group.
Cllr Colin Mann, leader of the Plaid group, said: “I will be seeking assurances that the confidential clauses used in settlement agreements are not used as a way of silencing whistleblowers, an issue that has been raised in the National Assembly and by MPs.
“I understand the need to protect information, for instance, that may be commercially sensitive. But agreements should not be used as a way of covering up information being released which may be in the public interest.
“I shall be seeking information from the authority on the difference between confidentiality clauses in settlement agreements and Non Disclosure Agreements (NDAs) or so-called gagging orders.
“I’d also be interested to find out if confidentiality clauses go right across the board in terms of all levels of employees.”
A spokesman for the council said: “These types of settlement agreements are not uncommon and many employers use them.
“Where confidentiality is necessary to protect the privacy or other rights of an individual, mutual agreement is sought and enacted through the use of such agreements.”
The reasons the council stated for confidentiality clauses were:
· Commercially sensitive information and information relating to commercial relationships.
· Confidential information relating to but not limited to any member, client, agent, supplier, investor and/or distributor of the council.
· Information relating to budgets, organisation and financial forecasts, development plans, employee and information.
· Financial information relating to the council.
· Research plans or results, development plans, projects or business plans relating to the Council.
· Information relating to the provision of any services by the council, quality control and certification procedures adopted or followed by the council.