A major Yahoo shareholder revealed that Scott Thompson allowed an inaccuracy about his academic credentials to go uncorrected for years.
Thompson's biography, including the one filed with the Securities and Exchange Commission, showed he had two bachelor's degrees - one for accounting, the other for computer science. In reality, he only has a degree in accounting.
The major shareholder who discovered the inaccuracy says he wants Thompson out by 9 a.m. PT Monday or the company will face possible legal action. But after the deadline passed, Thompson was still listed as CEO on Yahoo.com.
Yahoo said "the board is reviewing this matter and, upon completion of its review, will make an appropriate disclosure to shareholders."
The company has been losing ground to rivals Google Inc. and Facebook Inc. ever since, causing its revenue to steadily fall and leaving its stock price below $20 since September 2008, a few months after Microsoft's final offer.
The Associated Press contributed to this report.