Chairman De Villiers wants to make sweeping changes to men's tennis
The governing body of men's tennis expressed its relief after an anti-trust case brought by the German Tennis Federation (DTB) was thrown out.
The ATP faced the legal case after downgrading the Hamburg Masters from its elite status as part of schedule changes for 2009.
But after a two-week trial, a US jury said the decision did not constitute a breach of monopoly laws.
The DTB wanted £39m in damages from the ATP - and will now consider an appeal.
Though the ATP appears safe from the prospect of possible bankruptcy it faced had it lost the case, the DTB says it is waiting for written confirmation of the ruling before consulting its lawyers on whether to appeal.
"We remain convinced that the ATP illegally withdrew the Hamburg tournament's Masters status and we were right to challenge the decision," said DTB president Georg von Waldenfels.
These are exciting times for men's professional tennis with the ATP set to unveil the largest set of changes to the Tour since its inception in 1990
Etienne de Villiers
"The Masters status was awarded without a time limit and as long as we abide by the ATP's regulations this status must be renewed each year."
Following nine hours of deliberation, the jury in Delaware unanimously rejected claims that the ATP was illegally trying to monopolise the market for player services and tournament sanctions, and that the restructuring was the result of collusion between officials.
Chairman Etienne de Villiers said the court's verdict vindicated the ATP's plans.
"Both the jury and Judge Sleet have recognised and upheld our fundamental right to set and make changes to the ATP Tour calendar, changes that are necessary if we are to unlock the full potential of our sport," he said.
"Their decision also supports ATP's position that this process of change was undertaken in a transparent, rigorous and good faith manner.
"These are exciting times for men's professional tennis with the ATP set to unveil the largest set of changes to the Tour since its inception in 1990."
De Villiers unveiled plans at last year's US Open to replace the nine Masters Series tournaments with eight mandatory '1000' events - referring to the number of ranking points on offer to the winner.
It was proposed that Hamburg and Monte Carlo would lose their elite status, with a new event being added in Shanghai, but that prompted strong opposition from many officials and players.
De Villiers has come under increasing pressure in recent months, with Rafael Nadal and Roger Federer expressing their concerns about the way the sport is run.
Nadal, Federer and world number three Novak Djokovic have taken the unusual step of taking a place on the ATP's Player Council in order to make their views heard.
"There are many things about which we do not like how they have been done and by getting in (the council) we are going to try to hear about things before they happen," said Nadal.
"Because at the end of the day the council is set to represent players and not the president, as it sometimes seems to."
Federer stated: "We have to defend our interests."
Since the original plans were unveiled, Monte Carlo has been added to the 1000 series but not as a mandatory event, while officials from Hamburg - which is to be replaced in the calendar by a new clay tournament in Madrid - chose to take legal action.
But following the ATP's victory in court, Hamburg is set to be downgraded to the second-tier '500' series and moved to July - something they argue would cost them sponsor, ticket and broadcast revenue.