It is, explicitly said by the FSF: http://www.gnu.org/licenses/gpl.html http://www.gnu.org/licenses/gpl.html GPLv3: 6. Conveying Non-Source Forms. You may conv

It is, explicitly said by the FSF: http://www.gnu.org/licenses/gpl.html http://www.gnu.org/licenses/gpl.html GPLv3: 6. Conveying Non-Source Forms. You may convey a covered work in object code form under the terms of sections 4 and 5, provided that you also convey the machine-readable Corresponding Source under the terms of this License, in one of these ways: b) Convey the object code in, or embodied in, a physical product (including a physical distribution medium), accompanied by a written offer, valid for at least three years and valid for as long as you offer spare parts or customer support for that product model, to give anyone who possesses the object code either (1) a copy of the Corresponding Source for all the software in the product that is covered by this License, on a durable physical medium customarily used for software interchange, for a price no more than your reasonable cost of physically performing this conveying of source, or (2) access to copy the Corresponding Source from a network server at no charge. c) Convey individual copies of the object code with a copy of the written offer to provide the Corresponding Source. This alternative is allowed only occasionally and noncommercially, and only if you received the object code with such an offer, in accord with subsection 6b. GPLv2: 3. You may copy and distribute the Program (or a work based on it, under Section 2) in object code or executable form under the terms of Sections 1 and 2 above provided that you also do one of the following: b) Accompany it with a written offer, valid for at least three years, to give any third party, for a charge no more than your cost of physically performing source distribution, a complete machine-readable copy of the corresponding source code, to be distributed under the terms of Sections 1 and 2 above on a medium customarily used for software interchange; or, c) Accompany it with the information you received as to the offer to distribute corresponding source code. (This alternative is allowed only for noncommercial distribution and only if you received the program in object code or executable form with such an offer, in accord with Subsection b above.) FAQ mentions it: http://www.gnu.org/licenses/gpl-faq.html#RedistributedBinariesGetSource http://www.gnu.org/licenses/gpl-faq.html#RedistributedBinari... Also, take the quiz to test your knowledge of free software licenses! http://www.gnu.org/cgi-bin/license-quiz.cgi http://www.gnu.org/cgi-bin/license-quiz.cgi