"Quickie" divorce cases taken out in courts in England and Wales by 180 Italian couples have been declared void after a widespread fraud was uncovered.
A firm based in Italy was charging up to £3,700 to arrange the divorces, using 137 different county courts to cover their tracks.
Police found an accommodation address in Maidenhead, Berkshire, was used by 179 couples as proof of residency.
Under Italian law couples have to live apart for three years before divorcing.
In England and Wales, a couple who have been married for at least a year can apply for a divorce on the grounds of adultery, unreasonable behaviour or desertion without a wait.
Thames Valley Police found the fraud ran between August 2010 and July 2012 and each couple was being charged between 3,750 and 4,700 euros (£2,900-£3,700).
The problem was first identified in February 2012 by an member of staff at Burnley County Court. She spotted in two files, both involving Italian parties, an address was the same and that it was in Maidenhead, some distance from the court in Lancashire.
The accommodation address had been given by either the petitioner or respondent in the divorces.
In his judgement Sir James Munby, President of the Family Division of the High Court, ruled that "a decree, whether nisi or absolute, will be void on the ground of fraud if the court has been materially deceived, by perjury, forgery or otherwise, into accepting that it has jurisdiction to entertain the petition".
The ruling followed successful applications brought by the Queen's Proctor in relation to the "180 irregular divorces".
Sir James said he was being asked "to dismiss a large number of divorce petitions...obtained in consequence of what can only be described as a conspiracy to pervert the course of justice on an almost industrial scale".
He made it clear that the fact that one or both parties may have remarried, or even had a child - as had happened in one case - made no difference to his decision.
Statement of truth
Sir James made a number of recommendations in his judgement to prevent a similar fraud happening again.
He said people applying for a decree nisi - the court's formal approval of a divorce in principle - should be required to complete a statement of truth, and addresses used in divorce petitions should be cross-checked against other cases.
He added that the fraudulent cases may have been "facilitated" by the current situation which allows divorce petitions to be made at many different county courts.
By this time next year there will be fewer than 20 locations at which a divorce petition can be issued, Sir James said.