Out-of-home (OOH) companies or operators provide outdoor advertising services and products to advertisers and brands looking to promote products and services or reach targeted audiences. Approximately 100 of the 12,000 ad agencies are OOH specialists -companies on the larger end include Mediavest and OMD/OMG and on the smaller end include Billups and Grand Design. There are approximately 2,000 OOH billboard companies and 100's of other DOOH network operators - the largest companies are Lamar, Outfront Media, and Clear Channel Outdoor and on the smaller end include companies like Atomic Billboards and O2 Media.
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