Oando, with dual listings in Johannesburg and Toronto, said it would issue a statement in due course.
Its shares last traded at 5.99 naira in Lagos.
The regulator said it had carried out a comprehensive review of Oando after it received two petitions and found related party transactions were not conducted at arm’s length and discrepancies in its ownership structure.
A company source said the petitions centred around the ownership of some Oando shares bought through an investment vehicle at the time the company bought ConocoPhillips’ Nigerian business for $1.65 billion in 2014.
“The commission notes that the above findings are weighty and therefore needs to be further investigated. After due consideration, the commission believes that it is necessary to conduct a forensic audit into the affairs of Oando Plc,” the SEC said in a statement.
It said a team of auditors, lawyers, stockbrokers and share registrars would conduct the forensic audit on Oando to ensure independence.
The SEC said in July it was investigating Oando’s shareholding structure.