Foreign investors may not own small businessees as these are reserved for South Sudanese nationals only. 
"CHAPTER VIII - SPECIAL PROVISIONS  [...]
Provisions Not Applicable to Small Companies
Article 323. Provisions not Applicable to Small Size private Companies. [...]
(3)  For the purposes of this part, a company shall qualify as a small size private company where –
(a)  its turnover in respect of its last preceding accounting period, is less than such amount as may be prescribed by Order of the Minister in consultation with the minister of finance;
(b)  it employs not more than seven employees; and
(c)  its share capital does not exceed an amount to be prescribed by the Minister
Nationals Participation in private companies 
(4) Small size private companies shall be the domain of South Sudanese nationals only
(5) Medium and large size private companies shall be open to non-South Sudanese investors on the condition that financially able South Sudanese shall have not less than 31% shareholding in such companies
(6)  A Medium or large size private company shall be one whose share capital shall not be less than such amount as may be prescribed by the minister
(7)  Minister, for purposes of this section, means the Minister responsible for commerce.
[...]
CHAPTER X - COMPANIES INCORPORATED OUTSIDE SOUTH SUDAN. 
Provisions as to Establishment of Place of Business in South Sudan. 
360. Application.  
This Chapter shall apply to a foreign company only if it has a place of business or is carrying on business in South Sudan and for the purposes of this Chapter, “foreign company” means a company incorporated outside South Sudan. 
361. Meaning of “Carrying on Business”. 
(1) For the purposes of this Chapter, a reference to a foreign company carrying on business in South Sudan includes a reference to the foreign company – (a) (b) establishing or using a share transfer office or a share registration office in South Sudan ; or administering, managing or dealing with property in South Sudan as an agent, personal representative or trustee, whether through its employees or an agent or in any other manner.
[...]
368. Obligation to State Name of Foreign Company, Whether Limited and Country Where Incorporated.
(1) A foreign company shall – (a) (b) (c) (d) in every prospectus inviting subscription for its shares or debentures in South Sudan state the country in which the company is incorporated; conspicuously exhibit in legible characters on every place where it carries on business in South Sudan the name of the company and the country in which the company is incorporated; cause the name of the company and of the country in which the company is incorporated to be stated in legible letters in all Act heads and letter paper and in all notices and other official publication of the company; and if the liability of the members of the company is limited, cause notice of that fact to be stated in the English language in legible characters in every prospectus referred to in paragraph (a) and in all Act heads, letter paper, notices and other official publications of the company in South Sudan and to be affixed on every place where it carries on its business.  [...]" (

[...]" (Companies Act, 2012, Article 323)
Companies Act, 2012
[<a href="https://mojca.gov.ss/wp-content/uploads/2023/03/Companies-Act-2012.pdf">Act</a>],[<a href="https://www.state.gov/reports/2023-investment-climate-statements/south-sudan/">Other</a>]