The world’s oldest dog has officially been stripped of his Guinness Record title, the authority for all things world-record-breaking said Thursday.

Guinness has spent the last month investigating Bobi, a supposedly 31-year-old Rafeiro do Alentejo from Portugal, in response to a “number of veterinarians expressing concern and skepticism over the dog’s age,” according to previous AP reporting.

Bobi died about eight months after he was awarded the oldest dog title in February 2023.

They were "reviewing evidence on file, seeking new evidence, reaching out to experts and those linked to the original application,” Guinness World Records previously shared with USA TODAY.

The formal review results are in, with Guinness ultimately concluding that Guinness "no longer has the evidence it needs to support Bobi’s claim as the record holder,” according to a news release issued on Thursday.

Here’s what we know.

Who is Bobi?

Bobi spent his whole life in the rural Portuguese village of Conqueiros, about 93 miles north of the country’s capital of Lisbon. He lived his owner Leonel Costa and his family, USA TODAY previously reported.

Costa’s father decided that they could not care for the litter of four puppies Bobi was born into, because they already had too many animals. So, they decided to do away with the litter. 

“Unfortunately, at that time it was considered normal by older people ... to bury the animals in a hole so that they would not survive,” Costa shared with Guinness. 

Costa and his brothers were able to find Bobi alive nearby. He was lucky enough to escape, hiding in a pile of wood at their home.

The siblings kept the puppy’s existence a secret for as long as they could, but when the boys' parents discovered Bobi was alive, "it was too late to put him down, so Bobi became a part of the family,” Guinness reported. 

Bobi led a life full of love and celebration despite the rocky start. 

His family threw the senior dog “a lavish birthday party” with than 100 guests to celebrate his supposed 31st birthday. Bobi died about 165 days after his birthday celebration. 

He was described by his owner as "one of a kind" – adding that his family was "very happy and grateful to life for allowing us, after 30 years, to have Bobi in our daily lives."

Bobi's family hasn't publicly addressed Guinness' decision.

What did the formal review by Guinness World Records find?

The reason why Guinness World Records revoked Bob’s record title was because they couldn’t prove the canine’s age with the evidence provided. 

A central piece of evidence tied to Bobi’s preliminary application was 2022 microchip data from a government database that did “not require proof of age for dogs born before 2008.”

“With the additional veterinary statement provided as evidence for Bobi’s age also citing this microchip data, we’re left with no conclusive evidence which can definitively prove Bobi’s date of birth,” Mark McKinley, director of records said in a statement. 

Mckinley added that Guinness “simply can’t retain Bobi as the record holder and honestly claim to maintain the high standards we set ourselves.”

Will a new record holder be named?

Eventually, but probably not for a while. 

The investigation into Bobi’s age was one of the reasons for the move, with Mckinley saying that it would take a “long time for microchip uptake around the world to catch up with pet ownership. Especially, older pets.” 

“Until that time, we'll require documentary evidence for all years of a pet’s life, we'll continue to ask for vet and witness statements and we’ll also consider microchip data as well where available,” he said. 

Guinness is not currently in a position to confirm a new holder for world's oldest dog, but added that they “certainly hope that the publicity around the record title encourages pet owners from around the world to get in touch,” Mckinley said.