David Baga, Lyft’s chief business officer who oversees Lyft Business, will step down on Sept. 6. The company did not disclose a reason for the departure. 

Lyft said it is not initiating a search to replace Baga. The executive’s direct reports, Gyre Renwick, vice president of Lyft Business; Megan Callahan, vice president of health care; and Raj Kapoor, vice president of revenue and operations, will assume Baga’s responsibilities. 

Baga has been credited for building Lyft Business, which involves partnering with businesses like healthcare providers and travel companies to give their workers or customers rides, from one employee to more than 200 since he joining in 2015. Lyft Business now represents more than quarter of rides for the company, according to Lyft. 

“David helped pave the way for leadership in non-emergency medical transportation, and formed a comprehensive network of partners in the travel and automotive spaces,” John Zimmer, co-founder and president of Lyft, said in a statement. “Most importantly, David established a deep and talented team that will continue to work with incredible partners to bring transportation to their communities.”   

Baga’s departure is the third C-suite executive to leave the company this year. A month ago, Lyft’s chief operating officer, Jon McNiell, departed after about a year on the job. And in May, chief marketing officer Joy Howard left after less than a year to take a position at the password management company Dashlane. In both cases, Lyft did not replace the executives, but chose to divvy up their responsibilities among other employees—much like how it is handling Baga’s duties. 

The executive shakeups follow Lyft’s lackluster debut as a public company in March. After peaking at $78.29 per share just after the initial public offering, the company’s shares have tumbled to $49.49 in mid-day trading on Thursday.

Since its IPO, Lyft has been working to shrink the multimillion-dollar losses by attracting new riders and better matching them with drivers. In its second quarter, the company reported a less-than-expected loss of $644.2 million and updated its annual outlook to account for higher revenues and smaller losses than initially predicted. 

As far as its leadership team goes, Lyft has hired a number of lower-level executives this year. 

In May, the company hired Heather Freeland, vice president of marketing operations, from Facebook and Jabari Hearn, vice president of brand, from Google—both of whom took over Howard’s marketing responsibilities. And three months prior to that, Catherine Buan assumed the role of vice president of investor relations after leaving business software firm Okta, and Uber’s former chief audit executive, Michelle DeBella, became vice president of finance strategy. 

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