The Premier League has ratified Michael Owen's transfer to Stoke, the Potters have announced on their official Twitter feed.
The decision ends an anxious wait for Owen, who had been a free agent since leaving Manchester United at the end of last season.
It had been unclear whether the Premier League would sanction his move to Stoke because the Potters had 25 senior professionals on their books before he put pen to paper.
But a Premier League statement released on Wednesday afternoon said: "The Premier League Board has confirmed to Stoke City the registration of Michael Owen. Consequently, he can be included in their 25-man playing squad."
Owen, on his Twitter account, revealed his delighted at the news, writing: "It's official! Deal done. I'm a Stoke player. Can't wait to get going."
The striker agreed a one-year pay-as-you-play contract at the Britannia Stadium on Tuesday, just prior to the Premier League deadline for clubs to submit their 25-man squads for the first half of the season.
However, because he was signed after the August 31 transfer deadline the move was a test of rules brought in two years ago, partly to ensure clubs do not build up a huge number of senior professionals.
A Premier League club can only sign a free agent - which Owen is - if they have an unused place in their 25-man squad. More importantly, it is against the regulations to leave a space open for a free agent if a club has 25 or more senior professionals registered.
Although Stoke boss Tony Pulis moved Jonathan Woodgate, Ricardo Fuller and Salif Diao on over the summer, he also brought in Michael Kightly, Steven Nzonzi, Maurice Edu, Charlie Adam and Geoff Cameron as players aged over 21.
The only way Stoke had any chance of registering Owen after the transfer deadline was to bring him in before Tuesday's registration cut-off point and name him in their 25-man squad.
But the Premier League could have decided that the club tried to circumnavigate the transfer window and the squad system to register Owen and leave one of their other contracted players out in the cold.
Earlier on Wednesday, the Stoke chairman Peter Coates said he was expecting Owen to prove Sir Alex Ferguson wrong to allow him to leave Manchester United if his registration was processed.
"We are very pleased. Michael is a good guy and a natural goalscorer. He is also a very proud guy," Coates said. "He might feel he's been written off, and I think he might have a point to prove. "
Coates has bankrolled Stoke for the last few years and made some impressive signings, but the arrival of Owen represents the highest profile star he has attracted to the Britannia Stadium.
But he insisted the player's £25,000-a-week contract is no gimmick signing and added: "We don't sign players to raise our profile. We sign them to make us a better team and give us a better squad, and I hope it works out well for him."