The Threading Building Blocks (TBB) in
the open source version, (there is a
new commercial version, $299, don't
know the differences yet) is GNU
General Public License version 2 with
a so-called “Runtime Exception” (that
is specific to the use only on
creating free software.) I've seen
other Runtime Exceptions that attempt
to approach LGPL but enabling
comercial use and static linking this
is not the case.
According to this question threading building blocks is usable without copy-left restrictions with commercial use.
