Apple Watch import ban saga kicked off a decade ago by an early-morning email to Tim Cook

Apple's ongoing legal wrangling with device producer Masimo over the Apple Watch stems all the way back to 2013, a report claims, in an email to Tim Cook. The email triggered not only a new feature for the Apple Watch, but also a legal headache that would see the wearable device banned from sale in the United States.

Buried in legal documents is an email to Tim Cook from scientist Marcelo Lamego, sent in the early morning in 2013, reports Bloomberg. The email boldly claimed the scientist could help "develop the new wave of technology to make Apple the No.1 brand in the medical, fitness, and wellness market."

A mere 10 hours later, an Apple recruiter contacted Lamego, and he was working as an engineer at Apple within weeks, tasked with developing health sensors. Within months, Lamego asked to file a dozen patents for sensors and algorithms to measure a person's blood-oxygen level.

The problem with the situation was that Lamego was previously the CTO of Cercacor Laboratories, the sister company of Masimo.

The headache employee

The email and hiring is believed to be the reason why Masimo went after Apple, calling it part of Apple's employee poaching in its patent infringement suit.

Lamego worked for Masimo in 2003 as a research scientist, then became the CTO of Cercacor in 2006.

Masimo says Lamego didn't have knowledge of how to develop the blood-oxygen feature before joining the company, and instead used his experience gained at the firm to assist Apple. Lamego resigned from Apple months after joining, with Masimo alleging Apple got rid of him after getting what it needed for the sensors.

Apple employee Steve Hotelling instead explains the departure was due to Lamego not being a good fit with the company, citing stories of clashes with managers, demands of million-dollar budgets, and wanting free reign to hire engineers without needing approval.

Apple did previously approach Lamego before the email, doing so a year beforehand in 2013. It was a time when Apple executives met with Masimo to secure technology for the Apple Watch, but Masimo believes it was used by Apple to learn about its technology and to prepare to hire others.

Though Lamego didn't leave for Apple at that time, he apparently changed his mind after Masimo CEO Joe Kiani decided not to make him CTO of Masimo itself. Apple also hired on Masimo's former chief medical officer and 20 others.

Though the email may have been considered the smoking gun for Masimo's lawyers, it didn't really help during Masimo's main lawsuit against Apple. A senior Apple engineer testified that the blood-oxygen feature's development didn't actually start until months after Lamego left the company.