Licensing an idea to public? With my research, it looks like a patent doesn't really make much profit from it due to the high maintenance fee. So I'm thinking is it possible to license my idea to public (for free or way less money) so that anyone can integrate into their product while they can't register as their patent. Something like Creative Common for innovations. Is there such a method?
You are correct that it is quite expensive to patent something in U.S. law. Under U.S. patent law, once an idea is publicly published, if no one else has a patent application for the same idea that is pending, the idea enters the public domain and no one can obtain a patent of that idea. The publication become "prior art" with respect to any future patent application which cannot be protected by patent law. Of course, if you publish an invention which you discovered independently, that someone else already has a patent application pending for that will be approved the following week, the fact that you published it after the patent was applied for doesn't prevent the person with the pending patent application from having it approved. The term "invention" rather than "idea" is what I will use for the remainder of this answer, because there are many ideas which may not be patented, while the lion's share of patentable ideas are appropriately described as "inventions." But, understand that as used in this answer, the term "invention" is being used to refer to the concepts and ideas necessary to make the invention, and not to a particular instance of a product made using those concepts and ideas. When an invention is in the public domain, anyone can utilize the invention free of charge without a license. People who use the invention are not even required to acknowledge that you invented or discovered it. An invention is also not eligible to be patented if more than a year has elapsed since the first sale of a product using it. But, in that case, the invention can still be protected as a trade secret until it is voluntarily disclosed in some fashion to someone who is not subject to a non-disclosure agreement. (I say voluntary, because the fact that, for example, an unauthorized corporate spy sees the trade secret doesn't end the status of the invention as a trade secret.) Some inventions, are effectively publicly disclosed and published the moment that anyone looks at it closely. The patentable element of other inventions are invisible to an end user, or to observer of an end user. For example, if the invention involves something in the interior of a device, or the invention involves something not visible to the naked eye (e.g. a process for synthesizing an industrial chemical from other chemicals where the chemical formula of the ingredients and end result can't be determined without a microscope or analytical chemistry tests), merely showing someone a product made using the invention will not put it in the public domain. It is generally legal to reverse engineer or independently come up with an invention which is merely a trade secret. It is not legal to use a patented invention or process, even if it is not directly copied and is instead reverse engineered or independently discovered, during the lifetime of the patent. There is no straightforward way to put an invention into the public domain while retaining any right to acknowledgement that you invented it or otherwise exercise control through a licensing agreement without patenting it.
Under US copyright law, all works are protected by copyright except for US Government works. The concept of "public domain" is not legally well-defined, and is used colloquially to refer to government works, works whose protection has expired, works available to all, and works not copyrightable (such as scientific laws or old software). Under older copyright law, releasing a work without the copyright symbol effectively put the work in the public domain. One can simply say "I dedicate this work to the public domain", and that is typically taken to be enough. CC0 purports to do this (using more words). However, as far as I can tell, author rights under European law are so strong that it is simply impossible. Releasing works into the public law has to be consistent with other aspects of the law. If you grant an perpetual exclusive right to copy and distribute to a publisher, their right does not go away on your death (a right which they would not have with a real public domain work). A problem is that an author who makes such a dedication (a bare license) could revoke the license and reassert their copyright. They could be estopped from making that argument. As property, your heirs would inherit the copyright and could (try to) revoke the license. Presumably the courts would not allow them to pursue ostensive infringers. Nevertheless, your plan is neither trivial nor bullet-proof.
Am I correct to infer that content/data created by a US city have an open license (public domain if created by US city employees or open license if created by a contractor)? No. For example, Larimer County, Colorado created election administration software in-house rather than using an outside contractor to do so, and it would be lawful for it to license that software to other governments in a manner that helps recover its development costs. There is an issue over whether a city or state can copyright its municipal ordinances or statutes or regulations in a legally enforceable way when people have a legal duty to comply with them. Some courts have held that state statutes that are binding upon people can't be protected in that manner. Efforts of the West Corporation to protect its page numbering system that was widely used by courts to refer to public domain case opinions were mostly invalidated in litigation. An open question is that most municipal governments incorporate by reference in their ordinances Uniform Building Codes that are subject to private copyrights and are not terribly cheap to obtain copies of. Yet, every person doing construction work is bound to follow the enacted ordinance including the parts incorporated by reference.
When you license your IP (like a song) you can specify the terms and conditions of its use by the licensee, including revenue shares from any derived work. However, if, as your comment suggests, you grant an "informal" license, and later decide that you want to "firm things up" with a license having different terms, that's a matter you would have to either negotiate or litigate with your counterparty. If you want a common reference point for negotiation of this sort of license, you might have a look at compulsory license terms.
Whenever there is a license to share things, the license creator wants the license to be widely used, but absolutely does not want slightly different licenses that could be used to trick people, or that just cause legal problems when used. Normal copyright law applies. And for the reasons above, the GPL license as an example allows you to copy the license verbatim but absolutely doesn’t allow you to make any modifications other than changing who is the person licensing a work. I would be curious what happens legally if someone licenses something with a sneakily modified copy of the GPL and then makes claims against a licensee who assumed it was the original GPL.
The terms transfer IP rights only for the New IP, meaning that Customer would own the new stuff. Developer will still own their old stuff, but Customer will have the right to use the old stuff, depending on the license terms. If the license is as in your link, then it is forever (but this is a stub, so I assume that the license will be more specific and possibly restrictive). You retain all your rights to old stuff, customer will not pay royalties for the old stuff, and they can transfer or extend the license, or part of the license, to others.
You can't You agreed: by submitting Materials in any form to the Company, in addition to other provisions of the Terms, you automatically grant Company a royalty-free, world-wide, irrevocable, non-exclusive, and assignable right and license to use, copy, reproduce, modify, adapt, publish, edit, translate, create derivative works from, transmit, distribute, publicly display and publicly perform such Materials for the purpose of displaying and promoting the Materials on any website operated by, and in any related marketing materials produced by, the Company and its affiliates. They can keep and use your data forever and give it to whoever they want. The clause you quote doesn't alter that. All it says is that once a year, if you ask, they will tell you what information they shared and with whom. If they feel like it they will tell you how to get the information deleted.
The commentators are just making stuff up when they say that you can freely infringe on copyright as long as it is for personal use. It is true that "personal infringers" are less likely to suffer the legal consequences of any infringement (partly because it's easier to avoid detection and partly because the hassle to award ratio involved in suing a personal infringer is too high). It's a misunderstanding of "fair use", based on the legally erroneous assumption that anything is okay until you make a business out of it.