At the High Court, Justice Sir George Mann said it was clear MGN's criticisms were, on the whole, ill-founded.
He said Flitcroft, who says MGN found he was having an affair by hacking his voicemails, had "a real prospect of establishing that phone hacking played its part".
Eriksson believes his affair with television presenter Ulrika Jonsson was discovered through phone hacking.
In a statement to the Stock Exchange, MGN said the company "continues to contest the four claims vigorously".
Meanwhile, Google was ordered yesterday to block its search engine in France from providing links to images of a sadomasochist orgy involving Max Mosley, the former Formula One chief, in a ruling handed down by a Paris court.
The owner of the world's most-used internet search engine said the ruling would force it to create a "censorship machine", warning it would set a dangerous legal precedent for internet freedom.
It contends that the search engine is merely a platform that delivers links to content and it should not be responsible for policing them.
The ruling, which could influence broader European efforts to tighten web privacy rules, relates to nine widely circulated images taken from a video of the orgy that was filmed by the now defunct News of the World.
Mosley had sued in bid to get Google in France to filter the images and delete any links to them. Google is appealing against the ruling.