Like Fair Use, the doctrine of First Sale is listed in the copyright law (17 U.S.C. §109(a)) as a "Limitation on [the] exclusive rights" of the copyright owner.
In §106(3), copyright owners are given the right "to distribute copies or phonorecords of the copyrighted work to the public by sale or other transfer of ownership, or by rental, lease, or lending" (17 U.S.C. §106(3)). However, §109(a) limits that right:
"[T]he owner of a particular copy or phonorecord lawfully made under this title, or any person authorized by such owner, is entitled, without the authority of the copyright owner, to sell or otherwise dispose of the possession of that copy or phonorecord[.]" (17 U.S.C. §109(a))
Therefore, if you legally purchase a new book, and the copyright holder of that book receives his or her share of that purchase, you can lend or sell that book without asking permission from or sending money to the copyright holder. This right is what makes the lending library possible, and indeed, nonprofit entities like libraries are granted more flexibility in lending rights than consumers. Whereas consumers cannot lease out computer programs or audio recordings, libraries can (§109(b)).
The right of First Sale came up in 2013 with the Supreme Court case Kirtsaeng v. John Wiley & Sons, Inc. (No. 11-697 slip op. 03/19/2013) (PDF).
Supap Kirtsaeng, a Thai student studying in the US, supported himself through school by having his relatives in Thailand buy textbooks, which were the same as those published in the US but were sold for much cheaper. He resold these for a profit in the US, and the publisher of some of the textbooks, John Wiley & Sons, filed suit, claiming Kirtsaeng's first sale rights did not apply to works published outside of the US. This case made its way to the Supreme Court, and the Court ruled on March 19 2013 that first sale did apply to works published outside the country, and that Kirtsaeng was acting lawfully when he resold books published under the Wiley license in Thailand to students in the US. Had the Court gone the other way, this would have had serious repercussions for the resale of any work made in another country, including electronic equipment manufactured in Asia.
For more on the decision:
The information presented here is for informational purposes only and should not be considered legal advice.