"These people not only lose their jobs, they can face extreme difficulty finding employment elsewhere", the letter rants.
The Guardian could not independently confirm the memo, and the company did not respond to a request for comment on Friday.
Reports of a "Copper Gold" iPhone X came in thick and fast in the run-up to the launch of the handset back in September, however those claims never materialised. "We want the chance to tell our customers why the product is great, and not have that done poorly by someone else", Joswiak wrote in the memo. Employees will likely also fear leaking to correct inaccurate information being passed around publicly.
The memo was published as an internal company blog post. No, it's evil journalists that are making them do awful things.
Apple has long had a reputation for being the most buttoned-up tech firm around.
If the leaks don't stop, Apple warned potential legal action and criminal charges. Hundreds of software engineers were in attendance, and thousands more within the organization received details of its proceedings. "But the Apple employee who leaks has everything to lose". "Among those were Apple employees, contractors and some partners in Apple's supply chain". Last year, the company held a meeting with employees where it discussed how it plans to prevent leaks, talked about how leakers were caught, and answered employees' questions.
It reminds employees that when they're approached by press, analysts and bloggers they're "getting played".
"The success of these outsiders is measured by obtaining Apple's secrets from you and making them public", the company argues, wrongly. A scoop about an unreleased Apple product can generate massive traffic for a publication and financially benefit the blogger or reporter who broke it.
The overarching message of the memo is that "leaks are completely avoidable", but anyone who does leak to the press on objective can expect to be found by Apple's well-resourced security department and prosecuted to the fullest possible extent.
The impact of a leak goes far beyond the people who work on a project.
Every Apple launch is covered by the select press invited to such events like it's a holy event, and with a blinkered positivity from many about what are often deeply flawed products. A company-wide meeting or email, for instance, could be leaked by anyone. In the memo, Apple credits its own "investments" and digital forensics for helping it catch leakers.
"Within days, the leaker was identified through an internal investigation and fired". Multiple employees were caught sharing details about the iPhone X, iPad Pro and Airpods with a 9to5 Mac reporter, according to the memo.
But that doesn't mean that Apple is impervious to leakers, and the last 12 months have been a little worse than usual.
Leakers in the supply chain are getting caught, too.
The memo goes on to explain the work that Global Security, Apple's internal division focused on containing leaks, does to keep company information safe.