Foreign shareholding in companies providing land public transportation within cities by bus or metro is limited to 70% and 80% respectively, and subject to minimum capital requirement of SR500,000. Other transportation services, including freight transportation, are subject to discriminatory minimum capital requirement, but are not subject to foreign equity ownership limitations. 
"The Cabinet [...] Decides:
Modifying the list of types of activity excluded from foreign investment, issued by the Supreme Economic Council (canceled) by its decision No. (1-28) and the date of 5-3-1428 AH, by excluding from the services sector mentioned in that list, the following: [...]
Third: Land transportation services [...]" (Cabinet Resolution No. (103) dated 14-2-1440 A.H [23-10-2018])
-------------------------
"03.08 License for transport
This service is provided for international companies that wish to provide public land transport services. The Kingdom of Saudi Arabia provides many areas for investment in public transport services, namely:
1. Service for issuing license to practice bus public transportation within cities, under the service no. (03.08.01) of this manual.
2. Service for issuing license to practice metro public transportation within cities, under the service no. (03.08.02) of this manual.
3. Service for issuing license to practice other transport, under the service no. (03.08.03) of this manual.
03.08.01 Service for issuing license to practice buses land public transport within cities
-Service Description
This service is provided for international companies that wish to provide public land transport services by buses in cities in the kingdom of Saudi Arabia. [...]
-Service Rules and Restrictions
1. Consistency between the total percentage of the Saudi (shareholder / shareholders) and the capital according to the financial limits set forth for the type of activity in Section No. (11.04) of this manual.
2. The foreign company's average revenue (partner), for the previous three years prior to granting the license, shall be equal or more than 3 billion Saudi riyals. Company's assets value shall be 1.5 billion Saudi riyals at least.
3. The Foreign company (partner) shall be licensed in two countries at least, and at least 10 thousand employees.
4. The minimum capital required for the supply, operation and maintenance of the buses shall comply with Ministry of Investment practices for the services sector companies (500,000) SR.
[...]
03.08.02 Service for issuing license to practice land public transport by metros within cities
- Service Description
This service is provided for international companies that wish to provide public land transport services by metros in cities in the kingdom of Saudi Arabia. [...]
-Service Rules and Restrictions
1. Consistency between the total percentage of the Saudi (shareholder / shareholders) and the capital according to the financial limits set forth for the type of activity in Section No. (11.04) of this manual.
2. The foreign company's average revenue (partner), for the previous three years prior to granting the license, shall be equal or more than 3 billion Saudi riyals. Company's assets value shall be 1.5 billion Saudi riyals at least.
3. The Foreign company (partner) shall be licensed in two countries at least, and at least 15 thousand employees.
4. The minimum capital required for the supply, operation and maintenance of the buses shall comply with Ministry of Investment practices for the services sector companies (500,000) SR.
[...]
03.08.03 Service for issuing license to practice other transport
- Service Description
This service is provided for international companies 100% that wish to provide public land transport services in the kingdom of Saudi Arabia through the activities below:
- Taxi (public / private)
- Transfer "school - tourism - parameters - materials"
- Transfer of pilgrims and visitors from inside and outside the Kingdom
- Carriage of passengers by buses outside the Kingdom
- Directing taxis
- Car Rental - Trucks - Buses - Car Hire Brokers - Freight Brokers. [...]
-Service Rules and Restrictions
1. Presenting in 3 international markets for the same activity planning to practice.
2. Premium residence holders are exempted from the above documents.
3. Practicing for the same activity for more than 10 years in his country of origin, and the establishment shall be one of the establishments that provide a distinctive quality service in the field of road transport after evaluation by the public transport authority. 
4. The capital shall not be less than 10 million riyals.
5. Commitment to the implementation of all the organized commitments of the activity, including the standards and percentages of Saudization approved by the Ministry of Labor and Social Development and the establishment of a mechanism for that.
6. An entity, which relies on the provision of the service through technical channels, shall be excluded from the application of the above requirements.
7. In the event that the leasing activity "Cars - Trucks - Buses - Car Rental Brokers - Freight Brokers" without driver, the enterprise is excluded from applying the above requirements.
[...]
11.03 Types of Licenses, Minimum Capital Requirement and Percentage of Saudi Partnership [...]
9- Public transport (bus transportation within cities). Minimum Capital (SR): SR500,000. Minimum Saudi Participation: 30%.
10- Public transport (metro transportation within cities). Minimum Capital (SR): SR500,000. Minimum Saudi Participation: 20%. [...]
13- Practice of other transport activities.Minimum Capital (SR): SR500,000. [...]" (Ministry of Investment, Services Manual [8th edition], Jan 2020)
Cabinet Resolution No. (103) dated 14-2-1440 A.H [23-10-2018]
Ministry of Investment, Services Manual [8th edition], Jan 2020
[<a href="https://www.uqn.gov.sa/articles/1542315685232482500/">Resolution</a>],[<a href="https://www.misa.gov.sa/media/1128/moi-service-manual-8th-edition-en-v4.pdf">Manual</a>]