At a news conference Wednesday afternoon, investigators said Mobley works for a subcontractor that cleans Citizens Bank Park.
He is identified as Anthony Mobley, 54, from Yeadon, Pa.
Officials say the ring belonged to a front office manager, who has now been identified as John Brazer, the Phillies Director of Fun and Games.
Brazer reported the ring missing about 1:15 p.m. Monday.
He told police that he went into an executive bathroom, took the ring off and placed it on top of a toilet paper dispenser.
Brazer then said he left the office and it wasn't until he was traveling on I-95 that he realized he didn't have the ring. He returned to the office 40 minutes later and discovered the ring was no longer in the bathroom.
According to police, Mobley took the ring out of the bathroom shortly after it was left behind, and hid it in a supply closet by the hall of fame section of Citizens Bank Park.
There is limited access to that executive bathroom, and police obtained a list of those people who could go in there. They interviewed them one-by-one, and said came to Mobley Wednesday morning. Police say he confessed to taking the ring and hiding it.
At around 10:00 a.m., police say Mobley led officers to the closet where he hid the ring, and police found it was still there. Officers say it was wrapped in a towel and placed on a shelf.
The Phillies 2008 World Series Championship ring is valued between $10,500 and $18,000. It has 103 diamonds totaling 3.84 karats and made of 14 karat white gold. It is crowned with a ruby inlay topped with the franchise's signature "P". The team, coaches, managers and front office staff all received one.
In a statment Bonnie Clark, the Phillies Vice President for Communications said "It has been two agonizing days for the ring owner, so we are thrilled that the situation has a happy ending. The Philadelphia Police Department, particularly the South Detective Special Investigation Unit, did an outstanding job helping to swiftly solve the case."
Mobley is charged with theft and receiving stolen property.