evidence, typically deriving from an experiment or pilot project, which demonstrates that a ... the company was awarded the contract on the strength of evaluation, proof of concept, and budget proof of concept trials
confirmation in the form of a receipt or other document that one has paid for a particular item:we had to have proof of purchase in order to qualify for service under the warranty you need a proof of purchase otherwise the retailer cannot verify that you purchased the product from their store
a receipt or other document that serves as confirmation that one has paid for a particular item:we had to have proof of purchase in order to qualify for service under the warranty you need a proof of purchase otherwise the retailer cannot verify that you purchased the product from their store
evidence, typically derived from an experiment or pilot project, which demonstrates that a ... the company was awarded the contract on the strength of evaluation, proof of concept, and budget proof of concept trials