Franchise owners have complained that the machines have a “digital lock” preventing third-party repairs from being carried out.

Under US copyright law, it is illegal to bypass a digital lock that protects a copyrighted work, such as a device’s software, even where there is no copyright infringement.

The US Copyright Office has now granted an exemption covering the repair of “retail-level food preparation equipment”.

In a lengthy document published this week, the office explicitly cited the example of “a frequently broken soft-serve ice cream machine used in a restaurant”.

Meredith Rose, senior policy counsel at Public Knowledge, which pushed for the change, said: “Today’s recommendations are a victory for everyone — franchise owners, independent repair shops, and anyone who’s had to bribe their kids with a chilly treat on lengthy road trips.

“It’s been a long and rocky road to secure a right to repair, and while there are plenty of dips and twists ahead, today’s decision from the Copyright Office will lead to an overdue shake-up of the commercial food prep industry.”