Funny how one has to learn about this stuff months after it happened, just because one accidentally stumbles upon some link in the comment section of another meta post. That’s not OK. Also, I didn’t get any email telling me about this change and I wasn’t asked if I am OK with my content being re-licensed either.
As a reply to this post, I feel forced post my two cents here. Not only because this Q&A seems to be the appropriate place to do so, but also to clarify the legal parts that Stack Exchange Inc. seems to ignore.
License Notice
On September 5, 2019, Stack Exchange, Inc. declared it re-licensed all content from CC BY-SA 3.0 to CC BY-SA 4.0, including all previous contributions. The network's terms of service allows Stack Exchange Inc to use the material, as users provide a non-exclusive license to allow for commercial use among other purposes. However, it also makes clear that content is provided to other people viewing the site under the CC BY-SA license. Stack Exchange Inc's re-licensing announcement displayed at Stack Exchange and Stack Overflow have moved to CC BY-SA 4.0 makes clear that content was previously licensed under version 3.0. Pursuant to that license.
You may Distribute or Publicly Perform the Work only under the terms of this License.
Stack Exchange Inc does not have the right to unilaterally change the license of previously submitted content. Since I am the original copyright holder of my posts, Stack Exchange Inc. needs my permission to re-license. Without such permission, all my content remains licensed under CC BY-SA 3.0. As a reminder: under no applicable law are licensees permitted to bluntly re-license work which was provided to under a specific license by the licensor — me .
To be clear: I did not and do not intend to give Stack Exchange Inc. active or passive permission to re-license my content to another license; resulting in the fact that CC BY-SA 3.0 remains in effect for all my contributions.
Stack Exchange Inc. is generally welcome to express their objections and/or seek re-licensing allowance by contacting the copyright holder – me – in writing via email and postal mail. I would like to remind Stack Exchange Inc. about the fact that Stack Exchange Inc. has my email address on file. Any related contacting efforts via the Stack Exchange network itself, or any other means of communication, can and will be ignored.
Consequence
Based on the legal issues Stack Exchange Inc. introduced with their “re-licensing” and related action(s), I am herewith halting all further contributions to the Stack Exchange network websites. This is not likely to change, unless Stack Exchangr Inc. resolves the re-licensing issue they introduced by not asking for my consent as the copyright holder.
Reserved Rights
Being the copyright holder amd licensor of my posted content, I reserve all rights to enforce and secure my rights now and at any given time in the future if I deem it to be necessary to do so to protect my intellectual property against misuse by Stack Exchange Inc. or any other licensee. The licensee — Stack Exchange Inc. — is meanwhile given time to revert the unacceptable re-licensing, or to seek permission from me on yet-to-discuss terms and conditions.
Nota Bene
Last but not least I herewith benevolently remind Stack Exhchange Inc that one-sided contract changes are against the law and therefore generally void — even on an international level. Ignorance of that fact does not magically legalize unauthorized license change attempts.