A Professional Opinion Letter, sometimes known as a Legal Opinion Letter, is a letter written by an attorney or accountant essentially vouching for the authenticity of a company or organization.
The Certificate Authorities are quick to suggest a POL when applying for an Organization Validated or Extended Validated SSL certificate. And while the prospect of getting one may seem daunting, its convenience is undeniable–a POL can satisfy the majority of the requirements needed during the organization validation and extended validation processes. It can also satisfy three of the four requirements when applying for a Code Signing certificate.
If your company has in-house legal or a close relationship with a willing accountant, this is a very good option for expediting the validation process.