(Reuters) - Juul Labs Inc said on Thursday co-founder James Monsees plans to leave the e-cigarette maker, stepping down as an adviser and board member.

Monsees, who had previously been Juul's chief product officer, wrote to employees he was looking forward to spending more time with his family and pursuing other interests.

The company, in which Altria Group Inc () has a 35% stake, has come under intense media and regulatory scrutiny in recent times for its marketing practices and has also seen its valuation plummet.

Altria valued its stake in Juul at $4.2 billion as of end-2019, down from $12.8 billion in December 2018, as a string of vaping-related deaths coupled with increased bans following a surge in teenage vaping cloud the prospects of e-cigarette makers.

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