Can one enforce a patent while it is only &quot;pending approval&quot;? When does a patent begin taking effect, exactly? And if it takes effect BEFORE being officially approved (which seems strange to me), can the patent's author enforce the patent (for example, through demands to cease or negotiate, and filing of complaints with a professional body like the ACM) without communicating the content of the patent? This would seem to open the door to all kind of abuses.
Patents become enforceable when granted, not before. However there is something called provisional rights (absolutely nothing to do with provisional applications). In the US, under 35 USC 154(d), if a claim in a published application is “substantially identical” to a claim that eventually issues, a patent owner can get damages of at least a reasonable royalty on units produced between the publication and notice and the issue date. Enforcement on this must await the granting of the patent. The infringer must have actual notice of the published application. It is rarely invoked see this article.
The answer to the question "can so-and-so sue me?" is almost always "yes", regardless of context. Such a suit might be baseless, and it might get settled in your favor, but you still have to spend the time and money to defend yourself. This can be disastrous for a start-up that's trying to get off the ground, and it's how patent trolls make their money. (I'm not accusing SnapChat of engaging in such tactics as a rule, of course; I'm just pointing out that the legal system does allow for them.) Whether or not you are likely to be sued is a separate question, and one that can really only be effectively addressed by a trademark attorney with full knowledge of the particularities of your situation.
No, this is not true. Copyright can be enforced selectively. You are confusing copyright with trademark. Company can lose its trademark if they aren't protecting it. All the meanwhile they can choose to ignore some copyright infringement while enforcing their rights on others with no legal problems what-so-ever. In order to illustrate the difference: for example, if someone would make a clone of Super Mario and would call their clone as well "Super Mario" and maybe even would call themselves "Nintendo", even if they have programmed the whole game by themselves from scratch and the art and music would be all different, they wouldn't be infringing the copyright but challenging protected trademarks. In your case, the naming was identical, the art and everything was too similar to the original and therefore the clone was challenging the trademark that needs constant protecting.
In the US, the author would be able to wind an infringement lawsuit against the re-publisher. Title 17, the US copyright law codified, grants the author the exclusive right to authorize republication, and does not require that a person use their real name. The argument "It was on the internet, it's in the public domain" is utterly without legal merit. The same goes for the assertion that a person loses his rights if he is uncontactable. The author has stated the terms of the license, so there isn't even a reasonable argument that the infringement is innocent (unknowing: "I thought it was with permission). There is no requirement that you have to allow a potential user to hassle you about the license terms. The one thing that is special regarding anonymous and pseudonymous works is that under 17 USC 302, "copyright endures for a term of 95 years from the year of its first publication, or a term of 120 years from the year of its creation, whichever expires first". For a work whose author is identified, copyright "endures for a term consisting of the life of the author and 70 years after the author’s death". This assumes that the host site has not preempted author's license: Stack Exchange, for example, preempts an author's exclusive right, so you can copy stuff from here accorting to the SE terms of usage.
Alice has been developing her own enhancements, and they're pretty similar to Bob's. Neither Alice nor Bob has copied the other's enhancements, so neither has violated the other's copyright in the enhancements. Whether that could be proved in court is another matter, of course, but since the original work is licensed under creative commons the question unlikely to arise in court. Would Alice be prevented from coming up with enhancements to her own game if other people could prove they thought of and released the idea first? No. Copyright does not protect ideas. It only protects a particular expression of those ideas from being copied. Theoretically, if two authors come up with identical 500-word descriptions of something and can establish that each did so independently, neither has a claim against the other. The practical problem there, of course, is that it would be impossible to prove such a thing. Could Alice outright claim Bob's "Adapted Material" because he developed it on her original work? Assuming that in publishing his adaptations Bob followed the terms of the creative commons license with respect to the original work, Alice's only claim would be that he copied her adaptations without following the terms of the license. If Bob can show that he did not do so, her claim would fail. In a comment, you wrote: Suppose Alice went ahead and intentionally, somehow provably ripped off Bob's "Adapted Material" because she liked the content so much, does Bob reserve any rights on his adaptation, or is Alice able to commercialize the work that Bob did in extending her original work? If we assume that Bob complied with the license of the original material, we know that he licensed his adaptations under "the identical terms," so Alice would be able to use Bob's adaptations under those terms for non-commercial purposes. Since the assumption here is that Alice provably copied something of Bob's, I think it is fairly clear that she would be liable for damages if she exploited that material commercially without paying royalties.
A cease and desist letter is not binding or mandatory (for copyright infringement, and in most other circumstances). You are not required to send such a letter, and even if you do, any vague suggestion that compliance guarantees that the future plaintiff will not sue is non-binding. Such a letter simply warns the recipient of possible consequences of continuing the action. The closest connection to an enforceable cease and desist letter in the case of copyright infringement is that under DMCA, a plaintiff may send a certain kind of cease and desist letter to an internet service provider, and if they comply (etc.) the provider cannot be sued for contributory infringement.
In the most likely case No, but you can make it happen! First - almost every patent is rejected - at first. Then you respond to the office action rejection by arguing and/or amending and - guess what - you are likely to get a final rejection. That means the rejection is final until you pay them more money to file a Request for Continued Examination and get two more go-arounds with them. Can you keep doing this? Yes. A previous director of the USPTO tried to make a rule that limited the number of RCEs - the courts knocked it down. If you give up and let it go abandoned by not responding to an office action within the statutory limit (6 months) then the process of that application is over. If you have not filed a co-pending application before the initial application went abandoned then you are really starting over if you file a new application. The original application can be used against any new application on a similar subject matter if it has been published. But it might not have published. The law (35 USC 102) contains - (a) NOVELTY; PRIOR ART.—A person shall be entitled to a patent unless— (1) the claimed invention was patented, described in a printed publication, or in public use, on sale, or otherwise available to the public before the effective filing date of the claimed invention; or (2) the claimed invention was described in a patent issued under section 151 , or in an application for &gt;patent published or deemed published under section 122(b) , in which the patent or application, as the case may be, names another inventor and was effectively filed before the effective filing date of the claimed invention. Your application may or may not have been published. Then it is neither published or issued and does not fall under prior art under 102 or 103. Applications are automatically published by the USPTO at the 18 month point unless you requested non-publication. In that case if your application never issues it is never public and can't be used against you or anyone else as prior art. You could even decide to keep it a trade secret. Before the publication process came into being as part of TRIPS, an applicant could wait until they saw the claims that had been allowed and the patent was ready to go. If they didn't feel the claims were valuable enough they can chose to explicitly abandon and keep it secret.
So, as I understand the decision, it's a little more subtle than that. By default, states have sovereign immunity and can't be sued without their consent. Congress can remove ("abrogate") this immunity by law in some circumstances. They tried to do so for copyright infringement cases with the Copyright Remedy Clarification Act of 1990. However, in the present case of Allen v. Cooper, the Supreme Court held that this part of the CRCA is unconstitutional. The idea is that under the Fourteenth Amendment, Congress can abrogate state immunity when it's necessary to ensure people's right to due process, but only in a "congruent and proportional" way. Now if a state unintentionally or negligently infringes someone's copyright, that does not violate the person's right to due process, but an intentional infringement might. At the time the CRCA was passed, when Congress went looking for instances where states infringed on copyrights, they found several cases of unintentional or negligent infringement, and just a couple where they may have infringed intentionally. SCOTUS argued that to respond to this by completely abrogating state immunity in all copyright cases was disproportionate, and therefore unconstitutional. But the Court suggests in the opinion that Congress could pass a different law to abrogate immunity in copyright cases, if it were narrower. For instance, a law that only stripped immunity in cases of intentional infringement would likely be constitutional, especially if there were evidence that intentional infringement was happening enough to be a significant problem. So I think the answer is that as of right now, a state could deliberately infringe someone's copyright (e.g. by pirating software) and be immune from suit. However, Congress has the power to "fix" this, and most likely will, especially if there seems to be egregious abuse. (By the way, the decision contains an impressive quantity of pirate jokes. I guess since it's not only about copyright infringement (aka "piracy"), but actually alleges infringement of a video about a sunken pirate ship, the justices just couldn't resist.) Your "eminent domain" idea is separate from this. Seizing copies of the software wouldn't give the state the right to use them, as the software itself would still be copyrighted. The state would have to seize the copyright, and I don't know whether that is possible - it's not necessarily property in that sense. But if they did so, then they wouldn't be infringing the copyright at all (since the state itself would now own the copyright) and this case would be irrelevant. On the other hand, when a state uses eminent domain to seize property, they must as you say pay fair market value for it, and that means the market value before they seized it. So the value of the copyright in such a case wouldn't be "nothing" - it would be more like the amount a competitor would have had to pay the software maker to buy all the rights to that product. Likewise, if the state seizes your lovely house and bulldozes it to build a toxic waste dump, they owe you what someone would have paid for the house, not the value of a dump that nobody wants.