Arguments over the credit for a film are as old as the industry itself. Ironically, at first actors were insistent on not getting credits, embarrassed by their association with what was considered a fairground attraction. But as novelty grew into mass entertainment and art and - more importantly - into serious business, the tensions ramped up.
For most of cinema's existence, public awareness of film has been focused on stars. Despite the efforts of the Academy Awards and their national equivalents to redress the balance, there was little recognition that film was a team game.
The notion of film as a broad collaboration of talents was further hindered by the pervasive auteur theory in Europe. Since Truffaut first coined the phrase in 1954, the notion of the auteur, the single film-making vision that elevated the director above all, has been hugely influential.
Despite a backlash in the 1960s, the idea has retained a remarkable power over the international business - but it is now coming under serious attack. Wim Wenders, himself routinely described as an auteur, said recently that he accepted that the theories dominating European cinema in particular were failing to reflect the realities, to the detriment of certain disciplines, particularly the writer.
'I feel we can all learn how precious the relations between the director and writer are, the writer and the producer, and how precious that thing that the writer produces, the screenplay, is in the context of the European cinema as it tries to redefine itself, ready for the 21st century,' he said.
Of those relationships, the most clearly unequal is the one that exists between the writer and the director or producer.
The 60th anniversary of Cannes, this year, is seeing thousands of column inches (and megabytes) devoted to the grand auteurs who claimed the Palme d'Or. But few could name many of the screenwriters who authored some of those works.
There is now a significant percentage of regular film-goers who will go to see a film on the basis of the director, yet even among that sub-section, there is little if any conception of the writer's role.
Often in popular imagination, the writer is responsible for the dialogue, when often they have authored the work every bit as much as the writer in the theatre, where the script is honoured above all else.
Disputes have spilled over into the mainstream press, most recently in the acrimonious row between Guillermo Arriaga and director Alejandro Gonzalez Inarritu - long-time collaborators on films such as Amores Perros and 21 Grams - over Babel.
It will not be the last, largely because writers sense that there are changes in the industry that could work strongly in their favour. They include the advent of digital platforms, which offer new routes to audiences, in which everyone - writers, actors, producers and directors - is keen to take a bigger share.
There is also a growing belief that what the industry most needs is original ideas, but the best writers often gravitate more towards television, novels or the theatre where their work is recognised in credits and money.
'Manifesto is less as a weapon, more asan olive branch'
The thinking of writers now has a focus in the European Screenwriters' Manifesto. The document is drawing support from much further afield than just Europe - this week it was endorsed by The International Affiliation of Writers Guilds.
The articles include:
- Crediting the writer as 'an author of the work' in all materials, including marketing messages
- Protection of 'moral rights' including rewrites that distort the original
- Fair pay for every platform
- The right to paid involvement in the production process
- Fair access to state funding to develop work
Some areas will be highly contentious - one issue might be that of rewrites, particularly given the interest among some producers in Europe in adopting the team writing approach of the studios.
But the advocates insist that this is about strengthening the industry through fair recognition of the role of writers rather than antagonising directors or producers.
'For my part I see the Manifesto less as a weapon than an olive branch for creative equity and collaboration,' says Christina Kallas, president of the Federation of Screenwriters in Europe. 'After all, the document acknowledges the co-operative nature of the medium by describing the screenwriter as 'an' author, not 'the' author.'
Indeed, there has been high profile support from some directors, particularly younger ones, says Kallas. 'While directors from the older generation could remain unpersuaded - this is still to be seen - younger directors seem more open to sharing authorial credit.'
The stumbling block, or the great opportunity, is money, suggests UK writer William Nicholson, a writer on the Oscar-winning Gladiator. The status of the writer owes much to their position as a salaried employee of a film's producer, who is normally the person taking the financial risk.
'As long as we continue to be in that relationship to the project it will be hard to demand control over our work or even respect.
'The way forward if you really do want power is to function as a writer-director or even more as a writer-producer. If you want the power, you must be willing to shoulder the risk. If you don't want rewrites, be the boss,' he says.
'But we writers want to be free of all that, we just want to be free to write. As long as that remains our position, we will not have power.'
It is a historical fact. Mozart wrote what the Archduke wanted to pay for. 'The only way we can free ourselves from that is not to ask for money,' says Nicholson.