The Open Source Initiative considers the GNU GPL and LGPL to be approved licenses, which means that they meet their Open Source Definition. Criteria for qualifying as Open Source licenses include "No Discrimination Against Persons or Groups" and "No Discrimination Against Fields of Endeavor". From a legal point of view, software covered by any of the many Open Source licenses would be allowable for use in a corporate/commercial environment.
You are not even required to accept the GNU license before running the software, and even if you did, the license states that you are free to run it for any purpose.
The GNU General Public License and Lesser General Public License only address copying (or "conveying", in GPLv3 terminology), not use. In fact, you can use the software for any purpose you want, because you aren't even required to accept the license. From GPLv3:
9. Acceptance Not Required for Having Copies.
You are not required to accept this License in order to receive or run a copy of the Program. Ancillary propagation of a covered work occurring solely as a consequence of using peer-to-peer transmission to receive a copy likewise does not require acceptance. However, nothing other than this License grants you permission to propagate or modify any covered work. These actions infringe copyright if you do not accept this License. Therefore, by modifying or propagating a covered work, you indicate your acceptance of this License to do so.
A similar clause exists, for example, in GPLv2 (paragraph 5) and LGPLv2 (paragraph 9):
You are not required to accept this License, since you have not signed it. However, nothing else grants you permission to modify or distribute the Library or its derivative works. […]
Be careful, however, about sharing modified copies within the company. If, for example, your company has international subsidiaries, a case could be made that a customization made by Acme LLC in the US that is used by Acme Ltd. in the UK is a conveyance that is covered by the GPL. In that case, Acme LLC would be bound by the license.
Nevertheless, each party is explicitly granted permission to run the code by GPLv3:
2. Basic Permissions.
[…]
This License explicitly affirms your unlimited permission to run the unmodified Program. […]
And GPLv2 says this in paragraph 0 (emphasis added):
Activities other than copying, distribution and modification are not covered by this License; they are outside its scope. The act of running the Program is not restricted, and the output from the Program is covered only if its contents constitute a work based on the Program (independent of having been made by running the Program). Whether that is true depends on what the Program does.