The standards are virtually the same for double taxation agreements and tax information exchange agreements.
The difference lies in the extent of the details in the latter compared to the former. In both instances, the standards are the same and the authority to request and obtain information is very broad.
The taxpayer can protect information, if trade secrets are an issue. Otherwise, if the information is relevant to determining a company's taxable income here in Canada, then the taxpayer must disclose that information to tax authorities in the country who in turn convey that information to tax authorities here in Canada.
Obviously, certain basic considerations must be taken into account, such as protecting lawyer-client privilege, trade secrets and so forth.
Even if a country has bank secrecy rules in place, under double taxation agreements, such policies are not relevant. Despite the existence of bank secrecy rules, information must be disclosed under information exchange provisions. That is the benefit of negotiating these types of agreements with many countries that have bank secrecy rules in place. They cover a broad area.