Analysis Apple has, over the past few years, quietly and successfully patented, in the US at least, various aspects of Swift.

That's the programming language the iPhone-slinging biz open sourced in 2015 under the Apache 2.0 license with a Runtime Library Exception.

In the past day or so, developers working with the language have highlighted on Swift discussion forum Cupertino's intellectual property land-grab, expressing concern that the patents – which are assigned to Apple rather than the Swift project – may expose those writing Swift applications to future legal jeopardy.

Here are two of the patents in question: 9,952,841 and 9,329,844.

Setting aside the problems with software patents – many developers, among others, believe they should not exist – and ignoring the fact that many of the features mentioned in Apple's Swift patents (eg: options chaining) can be found in other programming languages, there's no concrete cause for alarm.

The Apache 2.0 license grants users the right to use patent-encumbered code from any contributor, including Apple; these rights terminate upon attempting to bring a patent infringement claim against any entity over a Swift project. Better still, Apple has not sued anyone for violating Swift patents, so far as The Register is aware.

At the same time, Google software engineering director and open source lawyer Daniel Berlin observed in a Hacker News discussion, the patent claims Apple has made are "worrying."

Google has cause to be wary given its bruising battle with Oracle over Java patents and copyrights – the patent claims were disposed of early on but the copyright case lingers on and Google is trying to reverse Oracle's victory in the US Supreme Court, which once before refused to accept the case.

Fears

Google has taken a shine to Swift and makes a significant number of code contributions. The ad giant has made Swift available for TensorFlow, and has been trying for more than a year to add Swift support to the official compiler for its upcoming Fuchsia operating system. Apple and Google haven't always got along so it would make sense for Google to be pondering what could go wrong.

The Register asked Apple about its patent strategy, just because we enjoy the ritual of sending email and having it ignored.

Commenting in the Swift forum earlier this month, Apple software engineer John McCall attempted to allay concerns by noting that Apache license grants users the right to use any patent implicated in contributed code.

"That grant is perpetual and irrevocable with regard to both all past contributions and all current contributions," he wrote. "Apple could, in theory, publicly declare at any point that its future contributions will no longer be licensed under the Apache license, and then it could pursue patent infringement claims against any users of versions of the Swift code that incorporate those future contributions."

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But McCall says that would drive people away Swift, which Apple has no intention of doing.

Ted Kremenek, Apple's senior manager of languages and runtimes, also weighed in, suggesting Apple's pursuit of patents is defensive – a plausible claim given how often patent claims get brought against Apple and other tech companies.

"Any company making a contribution to Swift is intentionally licensing implied patents to the project," he explained. "This is a business decision. Speaking on Apple's behalf, that business decision is clear and deliberate: we want Swift to be successful and to be used widely. The Apache 2 license provides a form of IP licensing as well as IP protection for the project, and thus its users."

There you have it, Apple's patent strategy is all about you: We patent for your protection.

Left unaddressed is a question posed by software developer Max Desiatov, who wonders whether a third-party open-source implementation of a Swift compiler or an open-source Swift-compatible language using patented features would be acceptable to Apple. ®