Asphalt 8: Airborne/Licensing Issues

Around early/mid-2017, the Porsche Update was released. Simultaneously, four "imitation Porsches " were removed from the Garage forever, though they were not removed from the game for people who already owned them. This was due to licensing issues with Porsche AG (Dr. Ing. h.c. F. Porsche AG).

Porsche Licensing Issues
In late 2016, Porsche AG's exclusive licensing agreement with EA (Electronic Arts Incorporated), where only EA was allowed to recreate Porsche cars in video games, expired.

Before this, several gaming companies, such as Gameloft (Gameloft SE), had been allowed to use imitation Porsches instead of "real" Porsches in their video games, due to a loophole in the licensing agreement with EA. Certain car-manufacturing companies, including RUF (RUF Automobile), 9FF (9ff), and Rinspeed, had created their own unique real-world cars by using the shells of Porsche cars, along with other design elements. Thus, these cars resembled Porsches, and would likely be indistinguishable from real Porsche cars in video games.

When the licensing agreement with EA expired, many gaming companies had to remove all imitation Porsches in order to be allowed to introduce real Porsches into their games. Thus, in Asphalt 8: Airborne, for example, four Porsches were indeed removed from the game, but only for people who hadn't purchased them yet.

[Note: Needs elaboration.]

Asphalt 8: Airborne and Porsche
During the Porsche Update, five brand-new real Porsches, including the Porsche 959, Porsche 718 Boxster S, Porsche Cayman GT4, Porsche 911 GT3 RS, and Porsche 918 Spyder with Weissach Package, were introduced to the game. Together, the Special Events for unlocking the vehicles were officially known as the Porsche Motor Series. The Special Events included three Championships, one Research & Development, and one Enduro Double Down.

When the five Porsches were added to Asphalt 8: Airborne, four "imitation Porsches" (the Rinspeed zaZen, RUF RT 12 S, RUF CTR 3, and 9FF GT9 VMAX) were removed from the Garage for players who didn't own them yet, due to licensing issues with Porche AG. These vehicles have never returned to the game and are likely to be unavailable for purchase indefinitely. These vehicles were all given away during four corresponding multi-stage Time-Limited Events during April-May 2017, with the vehicles for participation being "neighboring" vehicles in the Garage, as well as the imitation Porsches themselves. The giveaways required players to gain a position in the top 50,000 on the international Leaderboards at least 6 times and in the top 20,000 at least once, meaning that a definite number of these imitation Porsches was given away (albeit an extremely large number).

After the Porsches were given away in masses and then removed from the game, the Season 9 races of the RUF RT 12 S, RUF CTR 3 and 9FF GT9 VMAX were all removed entirely. For some reason, the Rinspeed zaZen's race was not removed. Collections which required Porsche vehicles were corrected to not include those vehicles, both for owners and non-owners of those vehicles. Mastery races for those vehicles were also removed, only for non-owners of those vehicles.

Toyota Aftermath
Later, the Scion FR-S (Toyota) and Toyota Supra RZ (Mark IV) were both removed due to licensing issues with Toyota (Toyota Motor Corporation), which had removed most of its cars from video games on the grounds that their cars were becoming "less popular" due to people preferring to drive the simulated versions rather than the real versions (which would cost money). As a result, the Asphalt 8: Airborne collection requiring the Toyota Supra was corrected to not include the car. Additionally, the Mastery races of both the Scion FR-S and Toyota Supra were removed for non-owners. Again, strangely, the Toyota Supra's Season 9 race wasn't removed. However, even more strangely, the Scion FR-S's Season 9 race was altered to have the Porsche 718 Boxster S function as the required vehicle. Now, there are two Season 9 races for the Boxster; this is almost certainly not intentional and will likely be patched out in a future update.

The previous phenomenon may be explained by changes made to the rest of Career Mode. Four races for the RUF RT 12 S and RUF CTR 3 (including two races in Versus Mode) were replaced with similar races for the Mazzanti Evantra and McLaren F1 XP-5. Additionally, after the Toyota Aftermath, the Scion FR-S's only Career Mode race was replaced with a similar race for the Boxster. It is likely that Gameloft accidentally coded the Boxster to replace the Scion FR-S in both its Season 4 and Season 9 races, instead of just its Season 4 race. The Season 9 race of the Scion FR-S was most likely supposed to be removed.

Currently, it seems unlikely that the Scion FR-S and Toyota Supra will ever return to Asphalt 8: Airborne. Currently, the only owners are those who had already purchased the cars before their removals. However, the Scion FR-S may return in a different form as the Subaru BRZ, which is currently a very popular car among Community Polls (for adding cars to the game).