July 28, 2021: -On Monday, Tesla CEO Elon Musk sniped at Silicon Valley neighbor Apple two times in a conference call to discuss Tesla earnings.

Although the companies don’t compete directly today, Apple reportedly builds an electric self-driving vehicle under a project code-named Titan and has attracted several engineers and executives away from Tesla. The Titan project is allegedly run by Doug Field, who returned to Apple in 2018 following the five years at Tesla.

When asked about the supply chain of Tesla, Musk said that there’s a misperception that Tesla uses a lot of cobalt, a key material in producing lithium-ion cells used in smartphones and electric cars.

“Apple uses, I think, nearly 100% cobalt in their batteries and cell phones and laptops, but Tesla uses zero cobalt in the iron-phosphate packs, and almost none in the nickel-based chemistries,” Musk said. “On on a weighted-average basis, we use 2% cobalt compared to, say, 100% cobalt of Apple. Anyway, so it’s just really not a factor,” he added.

Some cobalt mined in places such as the Democratic Republic of the Congo has been linked to human rights abuses like child labor. In 2019, in addition to Tesla and other major technology companies, Apple was named as a defendant in a human rights lawsuit, according to The Guardian.

In a conflict minerals report published this year, Apple said it publishes a list of all conflict minerals and cobalt smelters and refiners, and all of Apple’s cobalt suppliers participated in audits in 2020.

Later in the call, Musk cracked Apple’s so-called “walled garden,” namely because Apple strictly controls what software can be installed on the iPhone through its App Store. Apple’s walled garden faces scrutiny from lawmakers and other companies, which include in an antitrust trial that took place earlier this year after Epic Games sued it over App Store fees and policies.

“I think we do want to emphasize that our goal is to support the advent of sustainable energy,” Musk said. “It is not to create a walled garden and use that to bludgeon our competitors, which some companies use.”

Musk then faked a cough and said, “Apple.”

Musk said he likely would not appear on future Tesla earnings calls during the call unless he has “something significant” that he needs to say.