If McLaren were found guilty of possessing confidential Ferrari information, why have they not been penalised?
This is a very serious charge, and as such it carries very severe penalties, including being thrown out of the world championship.
But to apply those penalties, governing body the FIA would need conclusive proof that McLaren had used that information to their benefit, and the FIA says that did not exist.
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To impose in those circumstances the heaviest penalty of exclusion from the championship would risk a civil lawsuit, which the FIA would lose without cast-iron proof McLaren had used the information to their advantage. That would bring severe financial penalties to the FIA.
What exactly does being in "possession of Ferrari information" mean?
The ruling means that McLaren chief designer Mike Coughlan has been found to have a 780-page document of confidential Ferrari technical information, and that as teams are responsible for the actions of their employees, McLaren technically broke the rules.
But the FIA accepted McLaren's claim that they immediately suspended Coughlan as soon as they knew he had the Ferrari documents - and that at no point did the team use or benefit from the information in Coughlan's possession.
In a sworn affidavit as part of Ferrari's High Court case against him, Coughlan is reported to have said he showed the information to his colleagues, but they distanced themselves from the documents and insisted he destroy them. The ruling does not exclude that happening.
Ferrari, though, believe senior McLaren managers not only knew of the documents, but acted on them, too.
Are McLaren off the hook?
If they produce any parts for their car that appear to be a copy of - or made with reference to - anything that was in the information possessed by Coughlan, they risk being called back in front of the FIA and handed a severe punishment.
Equally, Ferrari are pursuing their lawsuits against Coughlan and their former performance director Nigel Stepney - who the team sacked because they believed he leaked the information to Coughlan.
Some in F1 suspect - and a suspicion is all it is - that some senior McLaren employees probably did know more about the Ferrari documents than the team is letting on
If those lawsuits throw up any new information that incriminates McLaren, then Ferrari can take the issue back to the FIA.
Do people in F1 believe McLaren got away with it?
Opinion is split.
Some believe, as McLaren boss Ron Dennis has contended, that the episode is more about personal ambition than industrial espionage - that Stepney and Coughlan were unhappy with their current roles and wanted to get more lucrative jobs with greater profile elsewhere.
According to this view, McLaren were inadvertently dragged into - and incorrectly besmirched by - a saga that fundamentally had nothing to do with them as a team.
Ferrari believe McLaren benefited from confidential information
Others suspect - and a suspicion is all it is - that some senior McLaren employees probably did know more about the Ferrari documents than the team is letting on, and possibly even acted on that information.
If they did, would that have been wrong?
According to the rules, yes. But that is not the same as saying it does not ordinarily happen in F1.
Engineers frequently move from team to team, and inevitably take with them the knowledge of what they were working on before.
Equally, teams are constantly observing the cars of their rivals to try to establish whether a) there is a part they could benefit from; or b) there is anything potentially dodgy about them. In either case, once that knowledge is established, teams inevitably act on it.
The problem with Ferrari's position is that their car was illegal
What is rare, though, is an engineer from one team having in his possession what appears to be a document containing almost a complete technical breakdown of a rival's car - as Coughlan appears to have had on the Ferrari.
However, if a team did come across such information, many familiar with the workings of F1 believe that team would take some advantage from it.
So are Ferrari right to be angry?
If they are right about the way McLaren used the information, probably. If not, no.
Among Ferrari's claims is that Coughlan was tipped off before the start of the season in March about the design of their car's floor.
The rules say this part must be rigid, but Ferrari's was flexing downwards, giving their car a marked aerodynamic advantage.
They say he passed that information on to McLaren colleagues, who passed the information on to the FIA, which then banned the floor.
It has since been made public that McLaren knew about the Ferrari floor because Stepney told Coughlan about it.
But this information is not relevant to the FIA charges against McLaren because it was separate from the documents - and pre-dates Coughlan getting them.
McLaren boss Ron Dennis insists his team have acted with integrity
Equally, in sporting terms the problem with Ferrari's position on the diffuser is that their car was illegal.
And there will be widespread astonishment at Ferrari complaining about the FIA's decision "violating the principle of sporting honesty" given the number of times they have been involved in contentious behaviour in recent years.
On top of that, there have been numerous occasions over the years when Ferrari have successfully had parts on the McLaren car banned in a similar manner.
Are Stepney and Coughlan being used as fall-guys?
Stepney has said he believes so. And as far as both are concerned, certain things do not add up.
Ferrari claim they found out Coughlan had the information when they were phoned by an employee from a Surrey photocopying shop to which Coughlan's wife had taken them.
Given that Coughlan was in possession of such sensitive documents, it seems odd he was not more discreet about it
Yet, given that Coughlan was in possession of such sensitive documents, it seems odd he was not more discrete about it.
However, McLaren's decision to suspend Coughlan suggests the team are innocent. To kick an employee out, one would imagine a company would have to be sure he was guilty and they were not, otherwise he would have nothing to lose by talking about what really went on.
F1 is often a whirl of conspiracy theories - and this case has sent them into overdrive.
Some have even wondered aloud whether the whole spy saga was started by Ferrari as an attempt to discredit and/or penalise their arch rivals when they were beating them for the first time in years.
Usually, though, conspiracy theories are found to be just that - and for now that is what they remain.
Is there more to come out?
Almost certainly. Ferrari are pursuing their court cases against Coughlan - in England - and Stepney - in Italy. It is hard to believe that more information about what has happened in the last few months will not come out.
How comfortable McLaren's senior managers feel about that only they know.
Have Ferrari made themselves vulnerable by so heavily criticising the FIA?
Theoretically, yes. In the past, teams and drivers have been hauled before the World Council to account for critical comments made about the FIA.
In practice, it is unlikely anything will happen to Ferrari in this case.