If you're a noob or even an advanced noob and want to make sure you license correctly, consider the following advice:
- **Actually use a license or waiver**. Code without a license/waiver is proprietary. Statement like "do whatever you want" or "public domain" is legally absolutely insufficient and is worth nothing.
- **If you're collaborating with other people, put on a license ASAP.** Any change in legal conditions require an agreement of all authors so if you're developing code with dozen of people and then decide to add a license to it, you have to contact everyone and get a permission, and of course that can get difficult with more developers.
- **DO NOT fucking write "all rights reserved" if you're using a free license** since that literally means you're NOT reserving all the rights.
- Know that normally **you cannot take back your permissive license**, i.e. if you actually release something under permissive terms under a correct non-revokable waiver/license, you cannot introduce stricter conditions later on. What you CAN do is relax and drop conditions (e.g. [copyleft](copyleft.md)) of a license later on. I.e. you can make something strict less strict but not vice versa.
- **DO NOT use your own license**. Use an existing one. Firstly you're not a lawyer and secondly even if you are, your license will be non-standard, untested in practice, possibly buggy, untrusted and missing from the usual accepted license lists.
- **DO NOT modify existing licenses**. You may add some conditions to the license if the license allows it and you should do it clearly, but do NOT change the text of the original license unless you change its name.
Miloslav Ciz
3 years ago