By Sean McLain in Tokyo and Nick Kostov in Paris
Nissan Motor Co.'s management has yet to give Nissan's board the complete version of a 170-page report detailing alleged wrongdoing by former Chairman Carlos Ghosn, drawing complaints from some directors, according to people familiar with the discussions.
Directors arrived at their scheduled board meeting on Monday afternoon expecting to get the full report, the result of an investigation dating to last year, and were surprised to receive a five-page summary instead, the people said.
When directors asked why they didn't receive the full report, they were told it was because the report had gained final internal approval only the day before and there had not been enough time to make copies. As of Wednesday, the directors still hadn't received the full report, the people said.
Some directors believe the five-page summary isn't enough to understand the allegations against Mr. Ghosn, said one of the people familiar with the discussions. "How can we ensure this doesn't happen again, if we don't know everything that happened?" said this person.
At their meeting, the directors told Nissan Chief Executive Hiroto Saikawa to resign. The resignation is effective Sept. 16. Mr. Saikawa will be replaced on an interim basis by longtime Nissan executive Yasuhiro Yamauchi while directors search for a permanent CEO.
After the board meeting, Nissan posted on its website a summary of the report's contents, adding that the full document was "highly sensitive" and couldn't be released. It said the directors had received the report, without saying whether they got the full report or a summary.
Asked why directors couldn't see the full document and when it might be distributed, a Nissan spokesman declined to comment.
People familiar with the proceedings said some at Nissan were concerned that the full report might be leaked to the news media if it were given to directors. One of these people said that the company had kept board members up to date on the investigation's findings.
The public summary of the report says that in addition to the Ghosn allegations, the internal investigation examined excess pay of more than $400,000 received by Mr. Saikawa. The summary says Nissan found its employees falsified documents to give Mr. Saikawa more stock-based compensation than he was due. It says Mr. Saikawa didn't know this had happened and wasn't responsible for misconduct. Mr. Saikawa also denied wrongdoing and said he would return the excess pay.
Nissan said it conducted the investigation with an outside law firm starting in October 2018, the month before Mr. Ghosn was arrested in Tokyo. The investigation, involving more than 100 people around the globe, found Mr. Ghosn hid the full extent of his compensation, used company funds to pay personal friends and had Nissan pay for perks such as a house in Beirut. Many of those allegations form the basis of criminal charges against Mr. Ghosn.
Mr. Ghosn says he is innocent of all the charges and didn't misuse company funds.
Nissan's current board was told that the board's audit committee intended only to look at potential wrongdoing by current or former directors such as Mr. Ghosn, Mr. Saikawa and former Nissan executive Greg Kelly. Mr. Kelly, who has been charged with helping Mr. Ghosn hide his compensation, says he is innocent.
A key difference between the full report and the summary given to directors is the number of names the versions contain. The full report includes the names of people who were parties to the alleged misconduct or worked to counteract it, while those names are lacking in the summary, said one of the people familiar with the discussions.
"Who are the people who helped Ghosn? Who resisted him? What happened to them? The board needs to know these things," another one of the people said.
The board also inquired about Christina Murray, the Nissan executive in charge of internal audits and compliance, who recently resigned. The board was told that she expressed a desire to leave Nissan as the investigation was winding down and had taken a job at another company. Ms. Murray didn't respond to a request for comment.
Write to Sean McLain at firstname.lastname@example.org and Nick Kostov at Nick.Kostov@wsj.com