Mr Yuan, who is also chief executive of the video-conferencing platform, moved roughly 40% of his stake in the company last week.
The shares were shown as gifts to unspecified beneficiaries last week.
Mr Yuan has seen his personal wealth rocket as Zoom became a household name during pandemic lockdowns.
An increasing number of students and professionals connected online boosting the fortunes of Zoom and its founder.
Mr Yuan started Zoom in 2011 and listed it on the US stock market in 2019, making him a billionaire. He is currently worth $13.7bn, according to Forbes.
A Zoom spokesperson said the transfers were related to Mr Yuan’s estate planning practices. “The distributions were made in accordance with the terms of Eric Yuan and his wife’s trusts.”
Zoom’s shares have nearly tripled in the past 12 months and the company has a market valuation of around $100bn.
“Zoom founder Eric Yuan’s decision to transfer more than a third of his stake will raise some eyebrows,” Edward Moya, at trading firm Oanda, told the BBC.
“While a Zoom spokesperson noted that the transfer is consistent with the Yuans’ typical estate planning practices, investors will be nervous until we find out who is the recipient of the stock,” he added.
“Yuan is only 51, married and has three children, so the distribution of his wealth could be viewed as rushed.”
Mr Yuan said working from home is here to stay even as lockdowns eased and vaccines are rolled out across the globe.
“The future is here with the rise of remote and work from anywhere change. We recognise this new reality, ” Mr Yuan said.
The video conferencing company expects sales to rise more than 40% this year, reaching more than $3.7bn.
However, Zoom said it did not expect growth to continue at the pace it enjoyed last year.
Chinese-American Mr Yuan was named the 2020 Time Businessperson of the Year and was included in its annual list of the 100 most influential people.