zlacker

The US Copyright Office notes that "Similarly, the Office will not register works produced by a machine or mere mechanical process that operates randomly or automatically without any creative input or intervention from a human author.", and lists in its examples:

> A claim based on a mechanical weaving process that randomly produces irregular shapes in the fabric without any discernible pattern.

That is so specific that I have to believe there was a court case where someone attempted to claim copyright for that kind of process.

But to answer your question to define algorithmically generated, the requirement is that “whether the ‘work’ is basically one of human authorship, with the computer [or other device] merely being an assisting instrument, or whether the traditional elements of authorship in the work (literary, artistic, or musical expression or elements of selection, arrangement, etc.) were actually conceived and executed not by man but by a machine.”

(Citation to: https://www.copyright.gov/comp3/chap300/ch300-copyrightable-..., see §313.2).