The GPLv2 and the LGPLv2 have language in them that says anyone who violates the terms of the licences immediately becomes non-compliant and does not have any means of redeeming themselves.

The GPLv3 gives an offender time to come into compliance, with there being mechanisms for licence reinstatement when compliance errors were promptly fixed.

Red Hat's Richard Fontana said in a blog post that the mechanisms for licence reinstatement — what he called the "cure language" — would be present in a file in the source code tree.

"The 'automatic termination' provision in GPLv2 and LGPLv2.x is often interpreted as terminating the licence upon non-compliance without a grace period or other opportunity to correct the error in compliance," Fontana said.

He pointed out that when the GPLv3 was published in 2007, the Free Software Foundation introduced a modified termination policy that included mechanisms for licence reinstatement where compliance errors were promptly fixed.

At that time, any projects under GPLv2 or LGPLv2 which wanted to avail of the mechanisms for licence reinstatement were required to adopt the new licence - GPLv3.

Said Fontana: "In 2016 the FSF, along with the Software Freedom Conservancy, announced the Principles of Community-Oriented GPL Enforcement – partly in response to tactics being employed by one litigant in the German courts.

"Among other things, the Principles call for extending GPLv3-style termination to GPLv2 works. By the end of 2017, over a hundred individual Linux kernel developers had signed on to a commitment advanced by the TAB (the Linux Foundation's technical advisory board) to extend the GPLv3 cure provisions to all users of the kernel.

"Then, in a series of announcements, 10 major technology companies led by Red Hat committed to extending the GPLv3 cure provisions to all their GPLv2, LGPLv2.1 and LGPLv2.0 code."

Fontana said this extension of licence termination policy was "because we consider it the right thing to do".