Apparently Such Files May be Distributes or Sold
Section 5.e of the Google APIs Terms of Service reads:
e. Prohibitions on Content
Unless expressly permitted by the content owner or by applicable law, you will not, and will not permit your end users or others acting on your behalf to, do the following with content returned from the APIs:
- Scrape, build databases, or otherwise create permanent copies of such content, or keep cached copies longer than permitted by the cache header;
- Copy, translate, modify, create a derivative work of, sell, lease, lend, convey, distribute, publicly display, or sublicense to any third party;
- Misrepresent the source or ownership; or
- Remove, obscure, or alter any copyright, trademark, or other proprietary rights notices; or falsify or delete any author attributions, legal notices, or other labels of the origin or source of material
It might seem that 5.e.2 prohibits the suggested use. But if the text is in fact in the public domain,"applicable law" (that is, copyright law) permits you, or anyone, to "Copy, translate, modify, create a derivative work of" or otherwise use the content. Thus 5.e.2 does not apply. Points 3 and 4 would seem to indicate that the source, including title and author information, must be included or preserved in the output files, but seems to be the only relevant restriction that applies.
Response to Comment
A comment by user Brian Drake questions the theory of this answer, stating:
The most you can say is that copyright law does not prohibit certain conduct (and even that is not clear: just because the text is in the public domain does not necessarily mean that the audio is in the public domain); this does not mean that copyright law expressly permits that conduct.
US Copyright law does not define what constitutes the public domain. Rather it defines what is protected by copyright, and specifies some cases in whch a work is not protected. (For nexample, 17 USC 105 provides tht works of the US Federal Government are not protected.) Anything not included in the protection of copyright is in the public domain. This has been confirmed by many cour cases and legal writings. Law generally follows the rule "Anything not forbidden is allowed."
Audio as Derivitive Work
An audio recording of a person reading a text aloud would be a derivative work of that text, and would normally have its own copyright, if created lawfully. (If the recording was of a text protected by copyright, made without permission and outside of fair use, it was not made lawfully and the infringer has no copyright in the recording at all.) But US courts have held that a work created by a mechanical or automatic process, including many computer programs, is not an "original work of authorship" and thus is not protected by copyright at all, and is thus in the Public Domain. The case of the "Monkey Selfie" is on point. ("Compendium of U.S. Copyright Office Practices, § 313.2" (PDF). United States Copyright Office. 22 December 2014. p. 22. "To qualify as a work of 'authorship' a work must be created by a human being.... Works that do not satisfy this requirement are not copyrightable. The Office will not register works produced by nature, animals, or plants."
Moreover, if the audio were protected by copyright, it would presumably be owned by the person who ran the program, and 17 USC 106 specifically grants the copyright owner permission to distribute copies.
The public domain consists of all the creative work to which no exclusive intellectual property rights apply. Those rights may have expired, been forfeited, expressly waived, or may be inapplicable.
As rights vary by country and jurisdiction, a work may be subject to rights in one country and be in the public domain in another. Some rights depend on registrations on a country-by-country basis, and the absence of registration in a particular country, if required, gives rise to public-domain status for a work in that country.
Definitions of the boundaries of the public domain in relation to copyright, or intellectual property more generally, regard the public domain as a negative space; that is, it consists of works that are no longer in copyright term or were never protected by copyright law. According to James Boyle this definition underlines common usage of the term public domain and equates the public domain to public property and works in copyright to private property. However, the usage of the term public domain can be more granular, including for example uses of works in copyright permitted by copyright exceptions. Such a definition regards work in copyright as private property subject to fair-use rights and limitation on ownership
*"How Can I Use Copyright-Free Works (in the Public Domain)?" by Nolo Press reads:
Copyright law gives creators certain exclusive rights. These rights include the exclusive ability to copy, distribute, and perform the copyrighted work.
But copyright is not infinite. Rather, it provides copyright holders with protections for a limited duration. When a work becomes available for use without permission from a copyright owner, it is said to be "in the public domain." Most works enter the public domain because their copyrights have expired.
The public domain includes every creative work that is no longer protected by a copyright, trademark, or patent. Creative works that are no longer protected are owned by the general public rather than the original creator. As such, the work is free to be copied, performed, or otherwise used by anyone.
"Public domain" works are not protected by copyright. The public owns these works, not an individual author or artist. Anyone can use a public domain work without obtaining permission, but no one can ever own it.
An important caveat regarding public domain material is that collections, new editions, and derivative works of public domain material may all be protected by copyright. With collections, an author could collect public domain works in a book or display them on a website, and the collection as a whole could be protected by copyright, even though individual works within it are not.
*"Welcome to the Public Domain" (Stanford libraries) reads in relevant part:
The term “public domain” refers to creative materials that are not protected by intellectual property laws such as copyright, trademark, or patent laws. The public owns these works, not an individual author or artist. Anyone can use a public domain work without obtaining permission, but no one can ever own it.
*"A macaque monkey who took now-famous selfie photographs cannot be declared the copyright owner of the photos" (AP) reads in relevant part:
A macaque monkey who took now-famous selfie photographs cannot be declared the copyright owner of the photos, a federal judge said Wednesday.
U.S. District Judge William Orrick said in federal court in San Francisco that "while Congress and the president can extend the protection of law to animals as well as humans, there is no indication that they did so in the Copyright Act."
- *NARUTO, a Crested Macaque, by and through his Next Friends, People forthe Ethical Treatment of Animals, Inc., v. DAVID JOHN SLATER; BLURB, INC., ; WILDLIFE PERSONALITIES, LTD." (Ninth Circuit full opinion April 23, 2018 No. 16-15469, D.C. No.
3:15-cv-04324-WHO) reads in part:
We must determine whether a monkey may sue humans, corporations, and companies for damages and injunctive relief arising from claims of copyright infringement. Our court’s precedent requires us to conclude that the monkey’s
claim has standing under Article III of the United States Constitution. Nonetheless, we conclude that this monkey—and all animals, since they are not human—lacks statutory standing under the Copyright Act. We therefore
affirm the judgment of the district court