It doesn't ad(d) up

Researchers in the US discover that advertising has no impact on short-term stock returns

If you thought outdoor advertising is the way to go to influence your firm’s short-term returns, you might want to read this report. Researchers Florens Focke, Stefan Ruenzi and Michael Ungeheuer challenge the view that a firm can influence or artificially increase stock prices through advertising. Information from the Wikipedia pages of firms in the US and their advertising and financial data shows that advertising significantly increases non-news-driven investor attention, but these are not economically significant. The report finds no impact of advertising on short-term stock returns.