UPDATE 2-Interpublic slashes organic growth forecast, shares fall By: Reuters: Company News October 24, 2017 at 10:57 AM EDT * Shares down 6.5 pct; other ad firm stocks also fall (Adds ad industry background, CEO comment, updates share price) Read More >> Related Stocks: Accenture Plc Amazon.com Facebook International Business Machines Interpublic GroupCompanies Omnicom Group Peoples Utah