To the best of our knowledge, all software in the TeX Live distribution
is freely redistributable (libre, that is, not necessarily gratis),
within the Free Software Foundation's definition and the Debian Free
Software Guidelines. Where the two conflict, we generally follow the 
FSF. If you find any non-free files included, please contact us
(references given at the end).

That said, TeX Live has neither a single copyright holder nor a single
license covering its entire contents, since it is a collection of many
independent packages. Therefore, you may copy, modify, and/or
redistribute software from TeX Live only if you comply with the 
requirements placed thereon by the owners of the respective packages.

To most easily learn these requirements, we suggest checking the TeX 
Catalogue at: http://www.ctan.org/tex-archive/help/Catalogue/ (or any 
CTAN mirror). Of course the legal statements within the packages
themselves are the final authority.

In some cases, TeX Live is distributed with a snapshot of the CTAN
archive, which is entirely independent of and separable from TeX Live
itself. (The TeX Collection DVD is one example of this.) Please be
aware that the CTAN snapshot contains many files which are *not* freely
redistributable; see LICENSE.CTAN for more information.

Anyway, just in case here a short overview of packages and licenses collected
so far (Aug 2015, might have changed since than) - "unknown" usually means
published somewhere without any license statement (but possibly with a 
copyright statement):

ANUfinalexam:				GPL+
abstyles:					Abstyles
adobemapping:				BSD
apa6e:						BSD
apalike2:					Knuth
ar:							LPPL
arpic:						Arpic
asana-math:					OFL
ascii-chart:				LPPL
authoraftertitle:			Public Domain
bbm:						unknown
bbold-type1:				unknown
bchart:						MIT
bera:						Bitstream vera
berenisadf:					GPLv2+ and LPPL
blacklettert1:				LPPL
borceux:					Borceux
braille:					LPPL
breakcites:					unknown
calligra-type1:				unknown
calligra:					unknown
charter:					unknown
cherokee:					unknown
chicago:					Knuth
cite:						unknown
clock:						GPL+
cm-unicode:					OFL
cmdtrack:					unknown
codepage:					BSD
context-filter:				BSD
context-mathsets:			BSD
context-rst:				BSD
context-vim:				BSD
context:					GPL+ or LPPL
courseoutline:				unknown
coursepaper:				unknown
crossword:					Crossword
csplain:					GPLv2+
dancers:					unknown
de-macro:					AFL
detex:						NCSA
din1505:					Bibtex
dk-bib:						GPLv2+
doc-pictex:					unknown
dosepsbin:					GPLv2 or Artistic
dotseqn:					Dotseqn
doublestroke:				Doublestroke
dvidvi:						unknown
ec:							ec
ecv:						unknown
eiad:						Public Domain
electrum:					GPLv2+ with exceptions and LPPL
elvish:						Elvish
epstopdf:					BSD
eqname:						unknown
esstix:						OFL
etex-pkg:					LPPL
eurosym:					Eurosym
facture:					CC-BY-SA
fancynum:					LPPL
fbithesis:					LPPL
figflow:					unknown
finbib:						Bibtex
floatflt:					LPPL
fltpage:					unknown
fltpoint:					LPPL
fonetika:					GPL+ and LPPL
font-change:				CC-BY-SA
formlett:					GPL+
framed:						unknown
free-math-font-survey:		unknown
fundus:						LPPL
fwlw:						unknown
gene-logic:					Crossword
gentium:					OFL
gentle:						CC-BY-SA
germbib:					Bibtex
getoptk:					CeCILL-B
gfsartemisia:				LPPL
gfsbaskerville:				LPPL
gfsbodoni:					OFL
gfscomplutum:				OFL
gfsdidot:					LPPL
gfsneohellenic:				LPPL
gfsporson:					LPPL
gfssolomos:					OFL
gillcm:						BSD
harvmac:					CC-BY
hc:							GPLv2+
hyph-utf8:					unknown
hyphen-basque:				Bahyph
hyphen-greek:				LPPL
hyphen-turkish:				unknown
hyphenex:					Public Domain
ifsym:						LPPL
inconsolata:				OFL
index:						LPPL
ipaex:						IPA
itrans:						BSD
jadetex:					MIT
jamtimes:					BSD
japanese-otf:				BSD
jlabels:					Bibtex or LPPL
kalender:					unknown
kixfont:					unknown
latex-tipps-und-tricks:		unknown
latex2e-help-texinfo:		Latex2e
lhcyr:						Lhcyr
localloc:					Bibtex
lshort-german:				GFDL
lshort-spanish:				GPLv2+
lshort-ukr:					GPLv2+
lua-alt-getopt:				MIT
magaz:						unknown
makeindex:					MakeIndex
mdputu:						BSD
menu:						LPPL
metapost-examples:			GPL+
mhequ:						Public Domain
midnight:					midnight
mil3:						unknown
minutes:					LPPL
mkgrkindex:					LPPL
mkjobtexmf:					GPLv2 or Artistic
mp3d:						LPPL
mpman-ru:					MIT
mslapa:						Public Domain
mxedruli:					LPPL
nature:						LPPL
newsletr:					Newsletr
ocr-b-outline:				unknown
ocr-b:						unknown
ogham:						Public Domain
oldstandard:				OFL
oubraces:					unknown
passivetex:					MIT
path:						Bibtex
pax:						GPLv2+
pb-diagram:					GPLv2+
persian-modern:				OFL
philokalia:					OFL
plain-doc:					Public Domain
plweb:						unknown
pnas2009:					Bibtex
preview:					unknown
prodint:					OFL
productbox:					unknown
ps2pkm:						MIT
psfrag:						psfrag
pst-bspline:				LPPL
psutils:					unknown
ptex:						BSD
punknova:					Punknova
r_und_s:					BSD
rccol:						LPPL
rsfs:						rsfs
russ:						unknown
seetexk:					MIT
setspace:					unknown
shapepar:					Dotseqn
showhyphens:				MIT
slideshow:					unknown
sphack:						Bibtex
stix:						OFL
subsupscripts:				LPPL
tabls:						Dotseqn
tds:						Latex2e
tetex:						GPL+ and GPLv2+ and LPPL
tex-refs:					GFDL
texdiff:					GPL+ or Artistic
texdirflatten:				GPL+ or Artistic
texdraw:					CC-BY
texloganalyser:				BSD
threeparttable:				Threeparttable
tie:						Latex2e
tikz-dependency:			(GPLv2 or LPPL) and (GFDL or LPPL)
tucv:						CC-BY-SA
tugboat-plain:				Bibtex
ulem:						unknown
umtypewriter:				OFL
utopia:						Utopia
venturisadf:				Utopia
version:					unknown
vntex:						Utopia
wadalab:					Wadalab
webguide:					Utopia
wsuipa:						Utopia
xdvi:						MIT
zed-csp:					Zed