As of yesterday, Ubisoft has started to reactivate some of the games that were previously deactivated. In an official statement, Ubisoft explained that they are only reactivating games that the user has played. However, they will continue to deactivate games that have not been played yet.
Source: IGN
Thanks Zero for the heads up

Original article:

Ubisoft have once again displeased their ever diminishing fanbase with a very annoying yet totally justifiable move. They have started to remove games from your library that have been bought from third party sites such as G2A or G2Play or other additional “ebay stores”. They have not offered a warning when doing this and users have simply woken up to an empty library. This is not the first time that a gaming industry has done this, however. Last year, Devolver Digital pulled the same move and started cancelling keys that were not bought straight from them. Games like Far Cry 4 and Assassins Creed Unity have simply vanished from users libraries and Ubisoft will offer no refund to these users.

You may think that Ubisoft have just decided that they no longer like people supporting them and that they want to dig themselves an even deeper hole with this move, and while that does seem plausible, the actual fact is that Ubisoft are well within their legal rights to do this and are in fact simply protecting themselves from theft. Sites likes G2A are notorious for cheap keys, but that is because they obtain them in legally questionable ways that nearly always violate the terms of the service in question (Steam, UPlay, Origin etc.). All is not lost for those of you who do like to use sites like G2A, however. While the risk with these third party sites is ever present, there are some officially licenced and approved sites for key selling that still offer a discount, just be careful when shopping.

While Ubisoft themselves will not offer a refund or even explaining themselves, users who were affected by this action can go to the retailer (G2A) directly and receive a refund. It has been reported that G2A were very co-operative and would provide refunds were necessary.

Ubisoft are within their legal rights to carry out this removal process, but one must wonder whether this is really going to protect their pockets or hurt them further. It is common knowledge that Ubisoft have made some terrible judgement calls as of late and have driven their fans away. This could put the nail in the coffin so to speak, because fans are very unhappy. Remember to be careful when buying games from 3rd party sellers, and hopefully you won’t be affected by any similar acts that may come in the future.

Has this affected any of you? How do you feel about Ubisoft simply removing games without warning? Would you still use a service like Uplay or purchase a Ubisoft product after this incident? Be sure to check out this open letter on the Ubisoft forums that is growing by the minute.