If an artist rented a licence to create animations for a game for only a month, then the licence runs out, then a few months down the track the artist decides to publish their game. How can the artist prove that they made those animations with licenced software?
If you are working for a company, you will usually have timesheets, basically some way of logging cost/expenditure against a project.
You can then compare this against the previously purchased licence.
If you are freelancing, it depends on many things, in Australia you need a "business number" and need to log your hours and any costs against that project ( the product licence for instance) as this effects tax.
If you have no record this will be hard, you could try and prove that your file windows time-stamps ( date modified ) were within the licence window, some programs also include "meta" tag information with time-stamps.......
You will need to be more specific for a more detailed answer.
Thank you for the response.
A friend and I are starting out as indie developers and I'm tasked with the graphics/animation side of things. So when we get to the point of selling the game on steam or some platform we hopefully won't run into licensing issues.