It was only last October that Toyota and fellow Japanese firm SoftBank, a major investor of multiple ride-hailing companies including Uber, joined forces to form the mobility company Monet. Since then, numerous other Japanese firms have jumped on board.

On Friday, Monet announced investments from Daihatsu, Isuzu, Mazda, Subaru and Suzuki. Each will acquire approximately 2 percent of Monet.

Honda and Hino joined Monet in March and will further invest in the mobility company to maintain their respective stakes of approximately 10 percent.

Each of the partners will provide data to be used to develop a mobility service integrating fully self-driving cars. The goal is to initially offer a ride-hail service in Japan for several public agencies and partner companies.

And by as early as 2020, Monet aims to launch an automated delivery service based around Toyota's e-Palette, a self-driving shuttle bus that was shown in concept form in early 2018.

Below is the latest share structure for Monet:

SoftBank: 35.2 percent
Toyota: 34.8 percent
Hino: 10.0 percent
Honda: 10.0 percent
Isuzu: 2.0 percent
Suzuki: 2.0 percent
Subaru: 2.0 percent
Daihatsu: 2.0 percent
Mazda: 2.0 percent