According to Google, it provides data only to outside developers it has vetted and to whom users have explicitly granted permission to access email.
Before you freak out, you should know that you've probably given your consent to those apps scanning your inbox, and, thus, having computers automatically go through your emails.
One developer called Return Path, a marketing company that offers free email organization tools, let its workers read about 8,000 user emails two years ago to help develop the company's software.
Although Return Path declined to comment on details of the incident, it did say it sometimes lets employees see emails when fixing problems with its algorithms. Gmail has almost 1.4 billion users globally - more users than the next 25 largest email providers combined.
Hundreds of app developers electronically "scan" inboxes of the people who signed up for some of these programs, and in some cases employees do the reading, the paper reported. No, it's not Google, this time around, but this privacy-infringing feature does affect Gmail, which happens to be the world's top email service.
Nearly exactly a year ago, Google promised to stop scanning your inbox to serve up ads in Gmail, but as the Journal's article details, executives of the vetted third-party companies claimed that their employees would read millions of emails and that it was "common practice".
A recent Wall Street Journal research has found that Google is not doing enough to prevent those developers from reading their users' emails, some of which even train their computers, as well as their employees for the job.
But everyone who spoke to the Journal confirmed that the practice is specified in their user agreements and they have implemented strict rules for employees regarding the handling of email. As part of the new updates, Google introduced a new search functionality that enables users to find settings and other info they might be looking for in their account, like how to change the password.
Google indicated that the practice was not against its policies.