A huge ad company just shifted $200 million of its TV money to YouTube — and the reason why ought to terrify TV execs

Ad-buying firm Magna Global has just shifted $200 million of the clients' money it usually reserves for TV ads over to YouTube, The Wall Street Journal first reported.

Known as an "upfront" deal, in total, Magna Global has committed to spending $250 million on YouTube ads over the next five quarters as part of a three-year partnership, the media buying company confirmed with Business Insider.

The first year of the agreement represents the "largest Google Preferred deal ever signed," Magna Global said in a statement.Google Preferred launched in 2014 and allows advertisers to reserve advertising spots from among the top 5% of YouTube's most popular channels.

Magna Global is responsible for around $37 billion in marketing investment, which it manages on behalf of clients including Johnson & Johnson, Coca-Cola, Sony, and CVS.

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