** Advertising firm Omnicom's OMC.N shares fall 2.2% to $79.50 premarket
** BofA Global Research downgrades stock to "underperform" from "neutral"; cuts PT to $77 from $87
** New PT implies a 5.3% downside to stock's last close
** Average rating of 13 analysts is "buy"; median PT is $103 - data compiled by LSEG
** OMC fell 6.2% in 2025
(Reporting by Anhata Rooprai in Bengaluru)
((Anhata.Rooprai@thomsonreuters.com))