Tata Sons, the promoter of major operating companies of the salt-to-software conglomerate, on Tuesday announced appointment of Cyrus P Mistry as its Chairman with effect from December 28 following retirement of Ratan N Tata. The Board of Directors of Tata Sons today announced the appointment of Cyrus P Mistry as the Chairman of the Board after Ratan N Tata retires on December 28, 2012, Tata Sons said in a statement. The Board has decided to confer on Tata the honorary title of Chairman Emeritus, it added. Mistry has been a director of Tata Sons since 2006 and was appointed Deputy Chairman in November last year. [caption id=attachment_561648 align=alignleft width=380