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

software hoarding
 n.

    Pejorative term employed by members and adherents of the GNU project to
    describe the act of holding software proprietary, keeping it under trade
    secret or license terms which prohibit free redistribution and
    modification. Used primarily in Free Software Foundation propaganda. For a
    summary of related issues, see GNU and free software.