It was the highest-grossing film of 2014 in the UK, holds a staggering rating of 96% “fresh” on the review aggregator site Rotten Tomatoes and has been widely praised as a pioneering example of how to mine movie gold from the most unlikely of corporate sources. But The Lego Movie still wasn’t good enough to make the US Academy of Motion Picture Arts and Sciences’ list of nominees for the best animated film Oscar.

In one of the biggest snubs of this year’s award season, Phil Lord and Christopher Miller’s flamboyant tale lost out to Big Hero 6, How to Train Your Dragon 2 and The Boxtrolls, as well as Song of the Sea and The Tale of the Princess Kaguya. In fairness, 2014 was one of the strongest years yet for animation – perhaps even the best since 2009, when Up, Coraline and Fantastic Mr Fox competed for the Oscar. But The Lego Movie was expected to challenge for the prize itself, not just place as an also-ran. The anger on Twitter has been palpable, and the snub has already been voted the year’s most spectacular by filmgoers.

What’s even more worrying than a fine movie missing out on its chance for glory – it would hardly be the first time a worthy film missed the Oscars cut – is the sense that the relatively new animation prize is continuing to take a decisive shift towards conservatism as it approaches middle age.

It wasn’t until 2002 that the Academy began to honour animated feature films with its own category, though Toy Story won a special prize in 1996 to celebrate its achievements with then-pioneering CGI. For seven out of the first eight years of the award being presented, only three movies picked up nominations, such was the perceived paucity of quality productions.

It did not take long for attitudes among filmgoers and critics to change. In 2010 six out of the top 10 highest-grossing films across the globe were animated. In the eight years between 2003 and 2010, animated movies were the best-reviewed wide release films seven times, according to Rotten Tomatoes. In the meantime the best animated film Oscar went to sublime Pixar fare such as Wall-E, The Incredibles and Up. These days there are more animated movies being made than ever before, which is one of the reasons we got The Lego Movie in the first place.

The other is that, like Transformers, GI Joe and Battleship before it, Lego is an enormous global brand with the potential to lure filmgoers into cinemas in huge numbers even when the end product is utterly horrendous. The fact that the film refused to follow in the footsteps of its half-cocked predecessors is exactly why it so deserves recognition from the world’s most important movie awards ceremony.

Could it be that The Lego Movie’s corporate origins continued to rankle with Academy voters, even as they were soon forgotten by viewers entranced by the boisterous tale of an ordinary construction worker mini figure who battles to torpedo the evil veil of conformity that has enveloped the once-vibrant Lego universe? This year’s selection seems to go in the exact opposite direction, with an emphasis on the delights of whimsy-packed stop motion (Laika’s admittedly-superb Boxtrolls), far out Celtic fantasy (Song of the Sea) and hypnagogic Studio Ghibli fairytale fable (The Tale of the Princess Kaguya).

These are movies that also deserve recognition – likewise Disney’s ultra-stylised, endearingly unexpected Big Hero 6. But surely The Lego movie might have slipped in ahead of How to Train Your Dragon 2, a fun fantasy sequel but one which, for me, lacked its 2010 predecessor’s soaring emotional impact?

If not, perhaps it’s time for the animation category to expand. Three nominees may not so long ago have been all the industry could muster in a given year, but when one of the best-reviewed and most-discussed movies of the year is missing out there’s an argument that five spots is no longer enough.

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