Hello and welcome to Business Daily here on the BBC World Service. I'm Ed Butler.

Now it is probably the biggest political scandal of the modern era,

but even today, the implications of Cambridge Analytica and what that consulting firm did

to a variety of elections around the world before it collapsed in 2017,

has yet really to be fully understood.

In essence, the critics say,

this firm of consultants ran a weaponised big data operation

to target to manipulate voters via the internet.

They use methods that threaten the very idea of free democratic debate.

Well, that is the argument anyway. The BBC's Jane Wakefield has been in Lisbon this week

at a noisy web summit where she's been speaking to one of the key figures in how the whole

scandal unfolded. She told me more about the background. Cambridge Analytica were a political consultancy,

but where they hit the sort of headlines was the news that they'd used the data of up to

87 million Facebook users, and then they used that information to sort of do psychological profiles

of people which could then be used in political campaigns.

There were suggestions that it was used in the Brexit campaign and there were suggestions that it was used in the US presidential elections of 2016.

And of course, following the scandal, we saw regulators around the world take action against Facebook,

saying that it hadn't taken the privacy of its users seriously enough.

We saw a five billion pound fine imposed by the Federal Trade Commission,

and regulators around the world are still looking at it.

And in terms of political advertising, we're still seeing the social networks grapple with how

they control it. We've seen firms like Twitter take under their own auspices the idea that

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