Kleiner Perkins Caufield & Byers, the investment firm that has backed tech companies from Google to Amazon, fired a woman junior partner after she complained of gender discrimination, her lawyer said at trial on Tuesday.
Former Kleiner partner Ellen Pao accuses the firm of firing her after she complained about harassment by a male partner. Kleiner has denied the accusations of discrimination and retaliation, and says Ms Pao underperformed her peers.
The case helped spark a broad discussion in Silicon Valley about sexism.
In San Francisco Superior Court on Tuesday, Ms Pao's lawyer Alan Exelrod said in his opening statement that Kleiner had promoted only one woman to senior investing partner by 2011, despite roughly 40 years in business.
“Was there a level playing field for Ellen Pao at Kleiner Perkins?” Mr Exelrod said to the jury. “We will prove to you in this case that there was not.”
Attorneys for Kleiner are expected to make opening statements later on Tuesday.
Since Ms Pao filed her suit in 2012, women employees at Pantheon Ventures Ltd and CMEA, two other venture firms, and a co-founder at Tinder filed similar suits that were later settled.
Many big technology firms have released statistics showing the percentage of their employees who are female hovers at around 30 per cent. They blame in part a dearth of qualified women to hire, but many critics say the firms are not doing enough to attract and retain women.
In her lawsuit, Ms Pao, now interim chief executive at social news service Reddit, said her standing at Kleiner deteriorated after she ended a brief affair with another partner, who has also since left the firm.
The firm says Ms Pao did not deserve a promotion and the better compensation that would have come with it, and that it has two senior women partners, more than most venture firms in Silicon Valley.
Ms Pao is seeking as much as $16 million from the firm, a lawyer for Kleiner Perkins has said. Kleiner could cite Ms Pao’s current compensation at Reddit to rebut her claim that she missed out on income by not moving upward at the venture firm.
