Blockchain-based proof of presentation of content on a media channel, including: a blockchain; a generator configured to generate at least first, second, and third parameters, wherein the first and second parameters are input parameters and the third parameter is calculated as an output parameter of a one-way cryptographic function, the generator configured to incorporate the first and third parameters into a first type of block and append the first type of block to the blockchain; an embedder configured to receive and embed the second parameter into the content to produce tainted content; and a probe configured to monitor the media channel for the tainted content and to extract the second parameter from the tainted content.