# How to invest in advertising as the sector enters a new age > Advertising spending is booming as AI transforms the industry, creating fresh investment opportunities beyond the tech giants. - Title: How to invest in advertising as the sector enters a new age - Summary: Advertising spending is booming as AI transforms the industry, creating fresh investment opportunities beyond the tech giants. The advertising sector is… - Keywords: advertising, investment, generative search, out-of-home advertising, digital advertising, alphabet, meta, amazon, wpp, publicis, jcdecaux, invest - Source: MoneyWeek — https://moneyweek.com/investments/retail-stocks/how-to-invest-in-advertising-as-the-sector-enters-a-new-age - Published: 2026-09-25T14:00:00+00:00 - Read time: 3 min - Topics: advertising, investment, ai, generative search, out-of-home advertising, digital advertising, alphabet, meta, amazon, wpp, publicis, jcdecaux ## Ghost adverts tell advertising's long story The "Take Courage" slogan painted on a London building near London Bridge has greeted railway passengers for nearly 100 years, part of a tradition stretching back thousands of years. ## Advertising began in ancient times Traders in ancient Egypt and Mesopotamia used clay tablets and papyrus posters, while stone adverts from ancient Babylon date back 3,000 years. ## Rome pioneered the advertising business Roman business owners commissioned designers to produce signboards as primary street advertisements, marking the beginning of what we now call the advertising industry. ## Newspapers fuelled advertising growth Weekly gazettes first appeared in Venice in the early 1500s and in Britain in the 1620s, with advertising helping to pay for printing and distribution from the start. ## The 1800s transformed advertising forever Mass production lowered costs and an affluent middle class emerged with discretionary income, creating demand for new products and accelerating advertising growth. ## Pears Soap pioneered brand marketing Thomas J. Barratt, chairman of Pears Soap, created early 1900s campaigns linking the product to aspiration, cleanliness and high-society status, earning him the title father of modern advertising. > Good morning. Have you used Pears' soap? ## Psychology shaped modern advertising In the 1920s, psychologists developed concepts of behaviourism and consumer emotions, refining strategies that exploited love, hate and fear to drive sales. ## Lucky Strike doubled women smokers Albert Lasker at Lord and Thomas agency created ads encouraging women to smoke instead of eating sweets, helping Lucky Strike increase market share by over 200% in its first year. > reach for a Lucky instead of a sweet ## Advertising spending tracks global growth Global advertising spending has risen from roughly 0.3% of GDP in the 2000s to around 0.8% today, with forecasts suggesting it could hit 1% by the end of the decade. ## Four tech giants dominate ad spending Alphabet, Meta, ByteDance and Amazon account for around 60% of global advertising revenue, up from 50% a few years ago, through their digital-native platforms. ## WPP is the UK's biggest ad agency Originally a wire basket manufacturer, WPP became an advertising holding company in the 1980s under Martin Sorrell and now operates as a one-stop shop for campaign coordination. ## AI search ads are exploding Advertising revenue on generative search platforms like ChatGPT is expected to reach $5.1 billion globally in 2026 and grow at nearly 100% annually through 2031. ## Out-of-home ads are holding strong While TV, print and radio spending decline, out-of-home advertising like billboards is holding its own because it guarantees human eyeballs see the message. ## Global Media dominates UK outdoor ads The private company manages over 253,000 outdoor advertising sites across the UK and Europe, with out-of-home revenue rising to £425.9 million and profits up 25%. ## JCDecaux leads global out-of-home The Paris-based company accounts for around 12% of the global out-of-home market, with 30% of assets in Europe and strong growth expected in underrepresented US and Asia markets. ## Publicis is the best agency operator Publicis has won key contracts and expanded data and consumer-identity capabilities to lead in digital advertising, with growth accelerating from 2.2% in 2026 to nearly 7% by 2028. ## WPP struggles after losing Sorrell Since Martin Sorrell left in 2018, WPP has faced multiple job losses and restructurings, with revenue falling from £11.4 billion in 2024 to £9.5 billion expected in 2026. ## Tech giants are becoming capital-heavy Alphabet, Meta and Amazon are funnelling hundreds of billions in advertising revenue into AI infrastructure, transforming from asset-light models into capital-intensive operations. ## Pinterest offers a niche opportunity Pinterest has grown into a top 25 advertising platform with 640 million users, generating around $1 billion in free cash flow against a $10.5 billion market cap. ## Key takeaway The advertising sector is shifting toward AI-powered search and out-of-home platforms, with specialist agencies and niche players offering better value than dominant tech firms.