A United captain adopted a puppy who was abandoned at a San Francisco airport, giving him a new home

• United Airlines says one of its captains adopted an abandoned dog at San Francisco's airport.
• A traveler left the dog after their documentation for the puppy to enter the US was deemed invalid.

Four months after a puppy was abandoned at an airport, the dog has found a new home — with a United Airlines employee and his family, according to the carrier.

Back in late August, the 6-month-old German Shepherd mix traveling with his previous owner from abroad was abandoned at a San Francisco International Airport's terminal, a representative for United Airlines told Insider.

According to the same source, the traveler left the puppy in the terminal after the Centers for Disease Control and Prevention (CDC) determined their documentation to bring the puppy into the country was invalid. CDC guidelines say dogs must meet certain criteria to enter the US depending on where they're traveling from, particularly if they are coming from high-risk rabies countries, and may need to quarantine upon arrival. United's statement did not specify where the dog was traveling from with its previous owner.

At the time, United flew the puppy — which airline employees named Polaris — to Los Angeles, where the dog was kept in a quarantine facility from September until early December, according to United's representative, who said there wasn't an adequate facility in San Francisco.

Following the puppy's quarantine period, United worked with the animal shelter San Francisco SPCA to find a new home for Polaris, United's statement said.

"United's Customer Service team took on quite a challenge to ensure Polaris would be safe, healthy, and find a loving home," Lisa Feder, SF SPCA's chief of rescue and welfare, said in the same statement.

Before the pup was approved to stay in the US, United employees at the San Francisco airport cared for Polaris by supplying him with food, treats, and toys, the airline representative said.

Then, earlier in December, United Airlines Captain William Dale and his family adopted Polaris.

"Polaris is doing incredible and adjusting to his new home," Dale told Insider. He added that he was "incredibly thankful" for the care the United employees at San Francisco International Airport gave to the puppy.

"Their hard work has made this a much easier transition for Polaris," he said. "We are so grateful for our new furry family member."

On December 15, United Airlines held an adoption party at the airport where Polaris was abandoned and donated $5,000 to the SF SPC. Polaris, dressed in a Santa costume, was of course in attendance, along with his new family.