The Jargon File (version 4.4.7, 29 Dec 2003):

hacker ethic
 n.

    1. The belief that information-sharing is a powerful positive good, and
    that it is an ethical duty of hackers to share their expertise by writing
    open-source code and facilitating access to information and to computing
    resources wherever possible.

    2. The belief that system-cracking for fun and exploration is ethically OK
    as long as the cracker commits no theft, vandalism, or breach of
    confidentiality.

    Both of these normative ethical principles are widely, but by no means
    universally, accepted among hackers. Most hackers subscribe to the hacker
    ethic in sense 1, and many act on it by writing and giving away open-source
    software. A few go further and assert that all information should be free
    and any proprietary control of it is bad; this is the philosophy behind the
    GNU project.

    Sense 2 is more controversial: some people consider the act of cracking
    itself to be unethical, like breaking and entering. But the belief that
    ?ethical? cracking excludes destruction at least moderates the behavior of
    people who see themselves as ?benign? crackers (see also samurai, gray
    hat). On this view, it may be one of the highest forms of hackerly
    courtesy to (a) break into a system, and then (b) explain to the sysop,
    preferably by email from a superuser account, exactly how it was done and
    how the hole can be plugged ? acting as an unpaid (and unsolicited) tiger
    team.

    The most reliable manifestation of either version of the hacker ethic is
    that almost all hackers are actively willing to share technical tricks,
    software, and (where possible) computing resources with other hackers. Huge
    cooperative networks such as Usenet, FidoNet and the Internet itself
    can function without central control because of this trait; they both rely
    on and reinforce a sense of community that may be hackerdom's most valuable
    intangible asset.


The Free On-line Dictionary of Computing (30 December 2018):

hacker ethic

    1. The belief that information-sharing is a
   powerful positive good, and that it is an ethical duty of
   hackers to share their expertise by writing free software and
   facilitating access to information and to computing resources
   wherever possible.

   2. The belief that system-cracking for fun and exploration is
   ethically OK as long as the cracker commits no theft,
   vandalism, or breach of confidentiality.

   Both of these normative ethical principles are widely, but by
   no means universally, accepted among hackers. Most hackers
   subscribe to the hacker ethic in sense 1, and many act on it
   by writing and giving away free software.  A few go further
   and assert that *all* information should be free and *any*
   proprietary control of it is bad; this is the philosophy
   behind the GNU project.

   Sense 2 is more controversial: some people consider the act of
   cracking itself to be unethical, like breaking and entering.
   But the belief that "ethical" cracking excludes destruction at
   least moderates the behaviour of people who see themselves as
   "benign" crackers (see also samurai).  On this view, it may
   be one of the highest forms of hackerly courtesy to (a) break
   into a system, and then (b) explain to the sysop, preferably
   by e-mail from a superuser account, exactly how it was done
   and how the hole can be plugged - acting as an unpaid (and
   unsolicited) tiger team.

   The most reliable manifestation of either version of the
   hacker ethic is that almost all hackers are actively willing
   to share technical tricks, software, and (where possible)
   computing resources with other hackers.  Huge cooperative
   networks such as Usenet, FidoNet and Internet (see
   Internet address) can function without central control
   because of this trait; they both rely on and reinforce a sense
   of community that may be hackerdom's most valuable intangible
   asset.

   (1995-12-18)