"In no case does copyright protection for an original work of authorship extend to any idea, procedure, process, system, method of operation, concept, principle, or discovery, regardless of the form in which it is described, explained, illustrated, or embodied in such work." - 17 U.S. Code § 102 - Subject matter of copyright: In general https://www.law.cornell.edu/uscode/text/17/102
"A computer program is a set of statements or instructions to be used directly or indirectly in a computer to bring about a certain result. Copyright protection for a computer program extends to all of the copyrightable expression embodied in the program. The copyright law does not protect the functional aspects of a computer program, such as the program’s algorithms, formatting, functions, logic, or system design." -- https://www.copyright.gov/circs/circ61.pdf
"17.25 Copyright—Affirmative Defense—Copyright Misuse Comment
The Ninth Circuit explicitly adopted copyright misuse as a defense to copyright infringement in Practice Management Information Corp. v. American Medical Association, 121 F.3d 516, 520 (9th Cir. 1997), amended by 133 F.3d 1140 (9th Cir. 1998). “Copyright misuse is an equitable defense to copyright infringement which precludes the copyright holder’s enforcement of its copyright during the misuse period.” Vernor v. Autodesk, Inc., 621 F.3d 1102, 1115 (9th Cir. 2010).The defense applies only when there is an allegation of copyright infringement. Altera Corp. v. Clear Logic, Inc., 424 F.3d 1079, 1090 (9th Cir. 2005). Although copyrightmisuse precludes enforcement of a copyright during the period of misuse, it does not invalidate the copyright. Prac. Mgmt., 121 F.3d at 520 n.9.
The misuse doctrine “forbids the use of the copyright to secure an exclusive right or limited monopoly not granted by the Copyright Office.” Id. at 520 (quoting Lasercomb Am., Inc. v.Reynolds, 911 F.2d 970, 977-79 (4th Cir.1990)). The purpose of the defense is to prevent copyright holders “from leveraging their limited monopoly to allow them control of areas outside the monopoly.” Apple Inc. v. Psystar Corp., 658 F.3d 1150, 1157 (9th Cir. 2011) (quoting A&MRecs., Inc. v. Napster, Inc., 239 F.3d 1004, 1026 (9th Cir. 2001)); see also Prac. Mgmt., 121 F.3d at 520-21 (holding that a copyright holder misused its copyright when it required a licensee to exclusively use the copyright holder’s copyrighted coding system, because that gave the copyright holder a “substantial and unfair advantage over its competitors”). -- https://www.ce9.uscourts.gov/jury-instructions/node/260
"Analytic dissection is a concept in U.S. copyright law analysis of computer software. Analytic dissection is a tool for determining whether a work accused of copyright infringement is substantially similar to a copyright-protected work.
In analytic dissection, unprotectable elements of a work are dissected out and discarded before making any comparison of the two works. These unprotectable components include idea (as contrasted with expression), scènes à faire (conventional elements typical of a genre), material in the public domain, and functional aspects. As the Ninth Circuit explained in the 1988 Data East case, that such elements are common to two works does not create substantial similarity. Rather, infringing similarity must be based on the similarity of what remains after the unprotectable elements are dissected out.[1]
Subsequently, in Computer Associates International, Inc. v. Altai, Inc.,[2] the Second Circuit applied this conceptual tool in determining whether two computer programs were substantially similar, under the name of the "Abstraction-Filtration-Comparison" test. As the Tenth Circuit concisely explained this test in Gates Rubber v. Bando Chemical Industries:
[A] court should dissect the program according to its varying levels of generality as provided in the abstractions test. Second, poised with this framework, the court should examine each level of abstraction in order to filter out those elements of the program that are unprotectable. Filtration should eliminate from comparison the unprotectable elements of ideas, processes, facts, public domain information, merger material, scènes à faire material, and other unprotectable elements suggested by the particular facts of the program under examination. Third, the court should then compare the remaining protectable elements with the allegedly infringing program to determine whether the defendants have misappropriated substantial elements of the plaintiff's program.[3]
This legal test has generally "been applied in subsequent [copyright law] decisions, to the extent that it is recognised in the USA, and elsewhere, as the accepted standard."[4]"
https://en.wikipedia.org/wiki/Analytic_dissection
"§107. Limitations on exclusive rights: Fair use Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include-
(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
(2) the nature of the copyrighted work;
(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
(4) the effect of the use upon the potential market for or value of the copyrighted work." -- https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title17-section107&num=0&edition=prelim
"Is a software company entitled to copyright protection for its unique programming platform; and, if so, under what conditions does a secondary use of that programming platform to create a new computer program constitute fair use?" -- https://www.law.cornell.edu/category/keywords/merger_doctrine
https://en.wikipedia.org/wiki/Abstraction-Filtration-Comparison_test#
https://en.wikipedia.org/wiki/Structure,_sequence_and_organization
https://en.wikipedia.org/wiki/Idea%E2%80%93expression_distinction#Merger_doctrine
https://www.copyright.gov/rulings-filings/briefs/google-llc-v-oracleamerica-inc-no-18-956-2020.pdf
https://www.congress.gov/crs-product/LSB10597
https://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-title17-section107&num=0&edition=prelim
https://www.ce9.uscourts.gov/jury-instructions/node/276
https://www.ce9.uscourts.gov/jury-instructions/node/260
https://www.law.cornell.edu/uscode/text/17/102
https://en.wikipedia.org/wiki/Monkey_selfie_copyright_dispute#Naruto_et_al_v._David_Slater
https://en.wikipedia.org/wiki/Neilson_v_Harford
https://en.wikipedia.org/wiki/Parker_v._Flook
https://en.wikipedia.org/wiki/Software_patents_under_United_States_patent_law#See_also
https://www.lexology.com/library/detail.aspx?g=51ec6bff-3b5c-4680-a8f4-44178a17c013
https://www.law.cornell.edu/uscode/text/17/102
https://law.stackexchange.com/questions/61743/intellectual-property-ownership-as-an-employee
https://lawgood.io/clause-bank/intellectual-property-employment
https://www.dbllawyers.com/copyright-law-the-works-made-for-hire-doctrine/
https://www.copyright.gov/circs/circ01.pdf
https://www.copyright.gov/help/faq/faq-general.html
https://www.copyright.gov/title17/92chap5.html
https://www.acc.com/sites/default/files/resources/vl/public/ProgramMaterial/20433_1.pdf#page=3.21