Prospective new Charlton owner Paul Elliott and lawyer Chris Farnell have both had their applications to take over the League One club rejected by the English Football League.
In a statement released on Friday, the EFL said three individuals were "subject to a disqualifying condition".
BBC Sport understands Elliott and Farnell are two of the three.
Charlton said they have lodged an appeal.
The precise reason for the decision is not known. However, it is understood that EFL officials have been trying to get proof of funding from East Street Investments, the company that bought Charlton from Roland Duchatelet in January.
ESI was originally owned by Tahnoon Nimer and Matt Southall but after the pair fell out and Nimer refused to put any more funding into the club, Elliott stepped in to buy it in June. However, in a court case the following month, Farnell admitted the sale had still not been completed.
Farnell's status has been the subject of increasing scrutiny amongst Charlton fans.
Police had to be called to his offices in Hale on Friday after a number of supporters gained entry and demanded answers about the running of the club. No arrests were made, although it was reported after the fans had been moved on that some pushing and shoving had taken place.
Former Southampton manager Dave Jones was in the office at the time discussing a role at Charlton, although it is understood it would not involve replacing any current members of staff.
BBC Sport has also established the Solicitors' Regulation Authority is investigating a complaint made about Farnell.
It is understood that allegations have been made that Farnell has conflict of interest by acting on behalf of both parties in the potential sale of the club.
Farnell has said on social media that the "accusation is not true". The SRA has indicated it could decide 'to commence a formal investigation which could lead to sanctions or restrictions' or it could choose 'to not take any formal action at this time'.
BBC Sport has been told Farnell's stake in Charlton would be minimal, that he and Elliott regard the EFL's decision as being related to a technical breach and an appeal has already been submitted.
Should the appeal not be successful, it would put Charlton and the EFL in a difficult position given the owners of the club would have no authority to run it on a day-to-day basis.
In their statement, the EFL said: "Every submission under the Owners' and Directors' Test is reviewed by the EFL using a variety of sources including external databases, and in appropriate cases, the EFL commissions external providers to conduct more detailed research."
Earlier on Friday, before the EFL decision was released, the Charlton Athletic Supporters Trust wrote to Elliot and urged him to "come clean" and explain why he had not met EFL regulations.
"We don't demand the release of commercially sensitive detail but surely, we deserve better than the fog of bland and empty reassurance that is all we have been offered so far," the letter said.