
SeeSaw, launched on 17 February, hosts more than 3,000 hours of free content from most of the major broadcasters, including Channel 4, Five and BBC Worldwide.
The content is supported by pre and mid-roll advertising sold by Video Initiatives, the specialist online video advertising arm of eType. It does not sell Channel 4 and Five inventory.
The COI, BUPA and Diageo are part of the 17 big brand names supporting the launch of the service, with advertising around programmes including 'Hustle', 'Hotel Babylon' and 'Doc Martin'.
Once the launch period is over, each of the launch advertisers will be presented with results from a research study, conducted with dres consulting and Continental Research, providing them with a unique insight into viewer-profile information and VoD usage habits.
The brands will also receive an exclusive comprehensive advertising-awareness and effectiveness summary.
Alan Greaney, Media Initiatives group chief executive, said: "The online video market offers an exciting new opportunity for brands to reach TV audiences online, and the sell-out proves the appeal of SeeSaw to advertisers."