3. Is there a ban on corporate donations to political parties?

Law of the Republic of Azerbaijan on political parties, 2023, https://www.venice.coe.int/webforms/documents/?pdf=CDL-REF(2023)012-e 

Election Code of the Republic of Azerbaijan, 2003 (as amended 2019). https://www.msk.gov.az/uploads/qanunvericilik/Election-code_2020.pdf

Corporate donations are not banned, but there are certain limits.

LPP prohibits obtaining donations by the following persons: local self-governing bodies and their subordinate institutions (Art. 23.2.2.) and other legal entities, including public associations and foundations, and religious institutions (Art. 23.2.3.). 

Election Code prohibits political parties from receiving donations from the following sources:  State bodies and municipalities (Art. 90.2.7.); state and municipal organizations and offices (Art. 90.2.9.); legal entities (including foreign interests), of which more than 30% of the charter (property) capital belongs to the state or municipality on the day of official publication of the decision to hold elections (Art. 90.2.6 and 90.2.9), military units (Art. 90. 2.10)., and charitable organizations, religious associations, institutions and organizations (Art. 90. 2.11).