AdAge has released their 2003 Global Marketing Report.
Sony is #10 in advertising spending worldwide, but only appears in the top 10 advertisers of 4 nations: Canada, New Zealand, Thailand and Ireland.
Sony and subsidiary companies also employ at least 10 different advertisers worldwide including: BBDO; Dentsu; Fallon; Grey; JWT; Saatchi; Y&R; TBWA; McCann; Bartle (see pg. 26.)
Full 54-page, 2003 Global Marketing Report .pdf