Rivian EV Pickup Truck.Adam Jeffery | CNBCA former female executive at Rivian is accusing the electric vehicle start-up of firing her for raising concerns about the company having a “toxic bro culture.”In a Medium post published Thursday afternoon, Laura Schwab, who joined Rivian late last year from Aston Martin, describes the company as a “boys club” in which female executives such as herself were left out of crucial meetings and marginalized.”Rivian publicly boasts about its culture, so it was a crushing blow when I joined the company and almost immediately experienced a toxic bro culture that marginalizes women and contributes to the company making mistakes,” she said. “I raised concerns to HR about the gender discrimination from my manager, the ‘boys club’ culture, and the impact it was having on me, my team, and the company. Two days later, my boss fired me.”Rivian spokeswoman Amy Mast on Thursday declined to comment on Schwab’s post and the allegations. She cited restrictions of the company’s quiet period as part of its IPO, which it filed for in August. The company is expected to list on the Nasdaq as early as next week.In a post on LinkedIn, Schwab also says that she has filed a lawsuit against Rivian for gender discrimination and retaliation.Schwab, who previously served as Aston Martin’s American division president, was hired last November as Rivian’s first vice president of sales and marketing. She was a high-profile addition for the company following a 20-year career with the famed British luxury brand as well as Jaguar Land Rover.Schwab’s post is called “Life Outside the Boys Club: Why I Spoke Up About Rivian’s Toxic Bro Culture (and Got Fired).” In it, Schwab says she was “excited” to join Rivian, but that excitement quickly turned to feelings of marginalization following an alleged pattern of exclusion among the company’s top male executives.”Despite my 20 years of auto experience, and my position as VP of Sales and Marketing, I was excluded from crucial meetings that impacted our mission and my team,” Schwab wrote. “Time and time again, I raised concerns regarding vehicle pricing and manufacturing deadlines, but no one listened, even though I have extensive experience launching and pricing vehicles. It wasn’t until my (often less experienced) male colleagues raised the exact same ideas that the Chief Commercial Officer would respond. Never in my years in the auto industry had I experienced such blatant marginalization.”It wasn’t immediately clear who serves as Rivian’s chief commercial officer, who Schwab says she reported to and was fired by. The company does not list such a position on its website or in its IPO registration form.Schwab alleges her boss said the reasoning for her firing was a “larger ‘reorganization.'” Schwab argues she was the only person “reorganized” though.”I pointed out that there was no coincidence in my firing and my raising concerns of bro culture and gender discrimination just two days earlier,” she said. “The very person I had flagged as promoting the discriminatory culture was the person who terminated me.”CNBC reached out to Schwab, who did not immediately respond for comment.