A former employee at Yahoo is suing a top woman executive at the company for sexual harassment, wrongful termination of employment and intentional infliction of emotional distress.

Nan Shi, who worked as a principal software engineer in Yahoo from February 2013, filed a complaint at Santa Clara Superior Court in San Jose, California, against her former boss Maria Zhang, a senior director of engineering at Yahoo Mobile.

Yahoo is also a defendant in the lawsuit, which was reported by the San Jose Mercury News for the first time.

China-born Shi alleges that Zhang forced Shi to have oral and digital sex with her on a number of occasions in Sunnyvale, California, in return for a "bright future" at Yahoo.

"While staying with Plaintiff, Zhang coerced Plaintiff to have oral and digital sex with her on multiple occasions against her will, even after Plaintiff told her she did not want to have sex,'' the complaint reads.

"Zhang told Plaintiff she would have a bright future at Yahoo if she had sex with her. She also stated she could take away everything from her including her job, stocks, and future if she did not do what she wanted.''

She also accused Zhang of unfairly downgrading her performance reviews for the second and third quarters of 2013, and removing her as a project lead. She was later put on unpaid leave and her employment was eventually terminated.

Shi informed the court that she complained about her boss' misbehaviour, but the human resources personnel at Yahoo were reluctant to investigate the matter.

Shi is seeking monetary as well as punitive damages.

"There is absolutely no basis or truth to the allegations against Maria Zhang. Maria is an exemplary Yahoo executive and we intend to fight vigorously to clear her name," a Yahoo representative told Reuters in an email.

Being a software developer by profession, Zhang founded the mobile company, Alike, which provides a mobile local recommendation app by the same name. Alike was acquired by Yahoo in 2013.

At Yahoo, she currently leads the mobile content and mobile SDK team for Yahoo's Mobile and Emerging Products division. She also leads the direction and execution of Yahoo Sports, Yahoo Fantasy Sports, Yahoo News Digest and the Yahoo mobile app.