Another high-level departure at Snap Inc. rattled investors in the social media company, which is losing its second chief financial officer in less than year.

In a regulatory filing Tuesday, the company said Tim Stone is leaving to pursue other opportunities. He had joined the Santa Monica, California, company just eight months ago after two decades at Amazon.com.

A number of top executives have left the company in recent months and a redesign of the platform roundly despised by users. Snap has been struggling with declining user numbers and stiff competition from Facebook's Instagram.

More instability in the top ranks of the company sent shares tumbling 12 percent Wednesday.

Wedbush analyst Michael Pachter said he is "troubled" by his departure and if he is leaving "because of an inability to mesh with other management" that could be a bad sign for the company.

The company said there have been no disagreements with Stone about accounting, management, operations, regulatory matters or other issues.

In November, Snap disclosed that it has received federal subpoenas related to a class-action lawsuit stemming from its 2017 initial public offering. The lawsuit claims that Snap misled investors about its user growth before going public. The company suggested at the time that regulators are looking into disclosures during its IPO about competition from Instagram.

The executive exodus "underscores a spate of challenges the company has faced as it squares off against Instagram and addresses ongoing challenges related to its app redesign," said Cowen analyst John Blackledge.

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