The new and improved Drapac, with a freshly minted Santos Tour Down Under WorldTour victory under their belts, will be there to fly the flag for Australia.
Also at the start line will be UCI WorldTour teams BMC, Etixx-QuickStep, Cannondale-Garmin, Giant-Alpecin, LottoNL-Jumbo, Sky, Tinkoff-Saxo and Trek Factory Racing.
Horner's latest landing spot, and probably his last, the American continental level Airgas-Safeway team missed selection but would have known that signing the aging 2013 Vuelta a Espana winner in hopes of an ATOC invite was always going to be a moonshot.
Unsurprisingly they missed.
The team is largely unknown and so are its riders. Think the majority of Australia's National Road Series teams and you'll get a good picture of its relative standing.
One look at the roster and you'll see it obviously has more work to do to compete at the level the ATOC dishes up each year. Horner aside, it was unlikely the team would have made much of a dent at the ATOC.
"I don't know what the promoters are thinking," Horner told Peloton magazine.
"They've obviously done harm to the race by not bringing me. You left the only current rider with a grand-tour resume who was going to show up, and I'm a past champion there.
"I figured we were already in. Clearly they didn't have to bring us, because we're not a WorldTour team or anything like that. We needed the invite and it wasn't a sure thing, but when you're putting on one of the biggest races in the US, you'd think you'd want the biggest US rider to go, so I figured it was a given.
"It was disappointing. It's one of the biggest races in the US and one I've won before, so I was ready to go there and I think we could have put on a big show. I don't think they've ever had a domestic team win California, and I think we could have won it. It would have been something special to do it with a purely domestic team."
ATOC decided to stick with local teams with better track records than gamble on one with a 43-year-old promise of doing something, which pretty much defined Horner's 2014 season with Lampre-Merida.
There his season was largely ruined when he was struck by a negligent motorist in Italy before recovering and going on to finish 17th at the Tour de France.
Then he messily finished his tenure at the Italian team after being forced out of a Vuelta a Espana defence with cortisol levels lower than the threshold demanded by member teams of the Movement for Credible Cycling.
Race directors and organisers have to balance a range of factors in their selections and the ATOC's brief includes developing American talent and exposing it to stiffer international competition.
It's hard to see how they have not fulfilled that obligation. And they may yet have an American winner in the 2013 champion at the start line, if he's selected to ride. BMC's Tejay van Garderen.
UCI WorldTour Teams
Trek Factory Racing (USA)
UCI ProContinental Teams
Novo Nordisk (USA)
UCI Continental Teams
Hincapie Racing Team (USA)
Jelly Belly/Maxxis (USA)
Optum/Kelly Benefit Strategies (USA)
Jamis-Hagens Berman/Sutter Home (USA)
Team SmartStop (USA)
SBS and Cycling Central will broadcast and livestream all stages of the 10-17 May 2015 Amgen Tour of California. Details TBA.