Pimblett threw 170 strikes to Gaethje’s 200, with a majority of the contest being contested on the feet.
Gaethje, 37, knocked Pimblett down twice on the way to securing the interim belt and a shot at Ilia Topuria at UFC White House on 14 June.
Pimblett is back in camp and aiming to return to action at UFC 329 in July.
The 31-year-old is waiting to be assigned an opponent but Frenchman Benoit Saint-Denis, currently on a four-fight winning streak, is rumoured to be the current frontrunner.
Pimblett says he is eager to have a rematch with Gaethje in future.
“I’ve got to show everyone why I deserved to get that title shot, show everyone that I’m going to be getting another one in the near future,” Pimblett said.
“I hope [Justin] beats Ilia so I can fight him again.
“That’s all I’m hoping for. He’s got a big ask, beating Ilia Topuria.”