Far Cry, Prince of Persia: Sands of Time and Rayman Raving Rabbids are the games in question, although no details have yet become available on the specifics of how or where the ads will be seen.
The news follows research that seems to indicate a general acceptance on the part of gamers that advertising in games is acceptable if realistic in full price titles.
But the differences with these titles are much older games that they are now free, so the players' impression is likely to be even more lenient.
There is no indication currently as to whether or not this is an idea that Ubisoft is trialling, or whether it's the start of a regular release of back-catalogue titles, and maybe a wider embracing of ad revenues as a whole.
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