Under the original UK proposals, there were three main criteria for judging qualification. Each element was awarded points with 16 needed from a possible maximum of 32.
* Cultural content - settings, British characters, subject matter and language - could gain a production a total of 4 points.
* Cultural hubs - locations, studios, effects, post-production and music - could earn 15 points
* Cultural practitioners - director, script, producer, composer, actors, cast, staff and crew - could earn the final 13 points.
Fiona Hotston Moore, managing partner at accountancy and tax specialist MRI Moores Rowland, explained that the proposed system meant a US production, for example, with little or no UK content or actors could shoot in the UK and use local facilities to gain 15 points and then cross the threshold with a point for being in English.
"The new cultural test means that the producer and director will have to be British to claim the reliefs,' Hotston Moore said.
Under the revised plans there is now a maximum of 31 points available but cultural content alone can take a film to the target of 16 points.
The cultural hubs element has dropped dramatically to just three points, while cultural practitioners falls to three points.
There is also a new qualification criteria, cultural contribution, which is a rather vague notion that a film should "contribute to the promotion, development and enhancement of British culture."
But it nonetheless attracts 4 points.
The British tax scheme has an annual budget of $227m (£120m) and will operate until 2012.
The tax break gives film production companies a cash payment of up to 25% of any tax loss on top of an extra tax deduction for certain production costs.