Mr Abubakar, who contested against Mr Tinubu in Nigeria's February 2023 presidential election, approached the States District Court for the Northern District of Illinois to subpoena Chicago State University for Mr Tinubu's school records, citing controversies over the president's background.
Records revealed that Bola Tinubu who attended Chicago State University in the 1970s was listed as female.
Mr Abubakar's request for the records is part of his legal challenge against the declaration of Mr Tinubu as Nigeria's president on March 1, 2023, following the hotly-contested February 23 election.
Mr Tinubu's legal team quickly responded by seeking to be added as an interested party in the suit, arguing that Chicago State University might not fully protect his interests as the owner of the records being sought.
In a motion filed on August 3, Mr Tinubu's attorney Christopher Carmichael argued that "Mr Tinubu should be allowed to join or intervene because he has a direct personal interest in records sought, his interests are not fully represented or protected by Respondent Chicago State University, and his interests will be affected if he is not permitted to join or intervene."
The crux of the matter lies in the privacy of student records, with Mr Tinubu's attorneys asserting that the records fall under a 1974 privacy law for American students.
They argued that Mr Abubakar's lawsuit indirectly seeks relief against Mr Tinubu by seeking records that the federal and state governments have determined should be confidential.
Both parties are anticipating an expedited hearing and disposal of the case, particularly as Mr Abubakar has indicated that a verdict from the Nigerian election petitions tribunal is expected around September 21, 2023.
Mr Abubakar had previously filed a suit before a county court in Chicago, Illinois, but withdrew it to file a more comprehensive case at the federal court. His legal team welcomed Mr Tinubu's motion to join the suit, indicating that their client did not oppose Mr Tinubu's intention to join the legal proceedings.