At its WWDC 19 developer’s conference earlier in the year, Apple showcased a number of new changes it made to its various operating systems.

It also touched on security and privacy, prompting the debut of its Sign in with Apple tool which adds anonymity and control when it comes to signing into different apps, which is often seen as a potential method for cyberattacks to take place.

On paper it sounds like a very handy solution, but according to a new lawsuit filing, Sign in with Apple violates the patent of another developer.

The one in question here is Blix, with its creation Blue Mail reportedly featuring a Share Email function from 2017 that Sign in with Apple has copied. In particular Blix notes that Apple’s tool operates quite similarly to Blue Mail, as it is able to share a public email address, while keeping your actual email address private.

If you’re wondering why we’re only hearing about this lawsuit now, considering Sign in with Apple was showcased a few months ago already, Blix is also accusing Apple of knowingly pushing down Blue Mail’s App Store ranking, to 143rd in search results, before recently being placed back to the 13th spot.

Added to this, Blix has disputed Apple’s claims that Blue Mail copied the features of another application, forcing the company to remove the app from the Mac-version of the App Store.

As such there is a lot of back and forth at this stage, with both parties laying accusations against the other.

Consequently we do not know at this stage how the legal proceedings will pan out, but it is looking likely that Apple will have to compensate Blix over the dispute, especially as it wants to retain such a potentially important new tool that’s been added to its operating ecosystem.

As this is a developing story, we’ll have to wait to see what the next steps from a legal perspective are.