10. Is there a ban on donations from corporations with government contracts to candidates?

Article 19, Decree-law of 2011-87, 2011, of the  organization of political parties: chapter 19 - Political parties are prohibited from accepting:
- Direct or indirect financing, in cash or kind, issued by any foreign entity.
- Direct or indirect financing from an unknown source.
- Aid, donations, and gifts issued by legal entities, whether private or public, with the exception of funding included in the state budget.
- Donations, gifts, and bequests issued by natural persons whose annual value exceeds sixty thousand (60,000) dinars for each donor.

Unofficial English translation.

There is a ban against donations from legal private or public entities.