Sorry, but the headline ("TPP makes copy left licences illegal" until the mods change it as linkbait) is nonsense. The actual affect of this section is appears to be to prevent governments ("Party" here pretty clearly means a party to the treaty - read "signatory" if that helps) from making proprietary software illegal.

We can argue about whether that's a good thing, but it has no effect on copyleft, as section 3(a) makes clear.