Iran Telecommunication Company / tci.ir sustains IP addresses rated up to "critical" for the amounts of spam sent during a 30 day period. Maintains CBL-listed, botnet-infected IP addresses during a 30 day period.
www.senderbase.org/lookup/org/?search_string=Iran%20Telecommunication%20Company%20PJS (bottom of pages)
whois: tci.ir / Telecommunications Company of Iran