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A Brief History of the $100 Billion SEO Industry

A logo showcasing the words s100b and SEO industry.
A logo showcasing the words s100b and SEO industry.

Today, the SEO industry is worth an incredible $100 billion and it’s still growing.


It comes down to its ability to reach customers. SEO lets companies grow their businesses online on their terms, without the restrictions of traditional advertising or the lack of attribution from other marketing methods. With a strong online presence, they can bypass antiquated technologies and distribution platforms and target the people most likely to buy from them.

Over the years, many commentators have predicted the demise of SEO, saying that “SEO is dead” or “search engine marketing is the SEO killer.”

Instead, SEO went from strength to strength, growing in size and importance with every passing year.

More of a visual type? Watch our $100 Billion Dollar SEO Industry video on YouTube.

Like to read? In this post we will discuss the origins of the SEO industry and how it evolved from humble origins into a multi-billion-dollar industry!

Just here for the TLDR? Skip ahead to check out our infographic covering a brief history of the SEO industry!

The Origins Of The SEO Industry – 1991 to 1996

Marketers typically associate SEO with Google. However, search engine rankings were on the scene several years before the world-famous tech company arrived.

The Origins of The SEO Industry

Launch Of The First Website – 1991

On August 6th, 1991 the very first website was launched.

With the first website came the first data categorizers. Remember Ask Jeeves, AltaVista and Yahoo!? They all categorized data, making it easier for users to find relevant content online in the early 1990s.

These platforms used “spiders” or crawlers to report their findings to a database, like a phone directory. Users would then enter search terms, and these systems would look up matching entries.

It turned out those early spiders weren’t all that useful. You had to know the website’s name for it to show in search results. It wasn’t until Lycos launched three years later that tech engineers solved this issue.

Historically, search assistants ranked pages based solely on content relevance. This way, users would see results most related to their search queries in descending order.

However, as webmasters added more pages to the web, it became harder to decide which order to rank them in, and the system broke down.

Yahoo! Launches – 1994

The original logo for Yahoo! wasn’t quite as exciting as its name.

Stanford University students Jerry Wang and David Filo launched Yahoo! in 1994, a search engine that would briefly become the most popular in the world.

Unfortunately, it was hard to use. In the first iteration, webmasters had to submit their pages manually for indexing so Yahoo! could match them to users’ searches. And even then, the system wasn’t quite as we imagine search engines today, often yielding irrelevant or unhelpful results.

Sergey Brin And Larry Page Launch Backrub – 1996

Jump to 1996, and a new type of search engine came along. Another Stanford University pair, Larry Page and Sergey Brin put their Ph.D. computer science degrees to use, launching a new service called BackRub from their dorm rooms.

The search engine promised a clean interface and an updated system for ranking pages. Instead of ranking pages by content alone, they started including the number of backlinks as a measure of popularity.

From the earliest days of SEO, backlinks have been vitally important, as search engines now use them to gauge a domain’s validity, relevancy, and authority.

Page wasn’t happy with the name, however. A year later, he changed Backrub to Google, and the rest, as they say, was history.

The Inception Of SEO – 1997 to 2005

Interestingly, it wasn’t until 1997 that the first recorded mention of the acronym SEO (search engine optimization) appeared online. It happened when a web marketing agency saw an opportunity to provide services to help brands rank higher in search results for business-related keywords. The idea was simple: firms would pay a fee and they’d get more website traffic in return.

The Inception of SEO

Because Google and SEO arrived in the same year (1997), the marketing industry began associating them. Search Engine Optimization was a way to rise through the ranks on results pages, just as Google’s platform started to dominate the market.

In those early days, SEO was simplistic. SEOs would submit page URLs to web crawlers (such as Google) to index and include relevant keywords to increase keyword density. However, this arrangement led to abuse where professionals would spam pages with the same keywords repeatedly to rank higher in results, forcing Google to respond.

The First Ever SEO Conference – 1999

As Google’s popularity grew, demand for marketers who could improve websites’ ranking exploded. Brands looked for professionals to give them more visibility using whatever means available.

In 1999, the first ever search marketing conference, Search Engine Strategies (SES), was launched. The meeting allowed industry specialists to share their knowledge and strategies more broadly.

Based on Google’s innovative algorithm, the main tactic was to build more links. Brands would pay agencies to host backlinks via syndicated third-party websites, increasing their apparent popularity.

Unfortunately for Google, the way agencies used these tactics detracted from the user experience. Agencies often placed spam links on low-quality or irrelevant websites, making domains appear to have authority when they didn’t. This was the beginning of black hat SEO and it forced the platform to evolve again.

Google Introduces Public Algorithm Updates – 2003

In 2003, Google began delivering algorithm updates publicly. These changed how the platform ranked pages, reducing the effectiveness of SEO methods that harmed the user experience. More reliable, trustworthy websites found ranking higher for their chosen keywords easier than those spamming the internet with garbage backlinks.

Google dubbed the first of these public updates “Florida.” It served as a benchmark for what was to come, fundamentally changing how the search engine calculated rankings.

Suddenly, SEOs had to focus more on user intent and expand visibility. Getting to the top of Google search results for specific keywords became a skill instead of a routine operation.

Florida also introduced brands to the danger of algorithm updates. While it aimed to reduce spam link websites, it also harmed the ranking of many innocent pages. As such it wasn’t a perfect system; a problem that would return in subsequent Google patches.

These factors combined pushed the demand for SEO services higher. Brands wanted partners who could protect them from down-ranking by arbitrary changes to the ranking algorithm and improve their content.

Google Launches The First Version Of Google Analytics – 2005

Fast forward to 2005, and the search industry became even more appealing with the introduction of Google Analytics. The new software made it possible for brands to track campaigns, measure traffic, and monitor the success of websites.

Consequently, this revolution made it easier for SEOs to offer clients defined objectives and provide clear proof of their successes. It also helped them analyze ongoing campaigns and convince website owners they should invest their marketing dollars.

SEOs saw this development as an opportunity to legitimize their services. Brands could see the help they were getting in real-time, encouraging them to retain their SEO services.

How Google’s Algorithm Updates Changed The Industry – 2006 to 2014

Google and SEO have long been synonymous and in the following years, Google launched a series of updates that had a tremendous impact on the SEO industry, fundamentally changing it for good. The core of all these changes was to deal with what the search giant perceived as “abuse” in the industry.

The Impact of Google's updates on the SEO industry

Google Releases The Panda Update – 2011

The purpose of Google’s Panda update was to reward websites offering high-quality content and punish those that weren’t. Also called the “Farmer” rollout, the search giant wanted to prevent websites from using duplicated text or content that didn’t say anything substantive.

Perhaps even more critically, Panda addressed content farming – websites that hired dozens of low-wage writers to create short articles covering various web queries. Google disliked their lack of authority and inability to provide users with nuanced or accurate content.

Google Releases Penguin – 2012

A year later, Google released Penguin, another alteration to its ranking algorithm, again designed to reward high-quality websites as it helped diminish the presence of those using manipulative link schemes.

The update effectively ended the last vestiges of traditional SEO in the sense of outsmarting Google, forcing the industry to focus on building more natural link footprints.

Panda and Penguin inspired the first cries of “SEO is dead!” as well as some pretty nifty merch…

Google Releases Hummingbird – 2013

Finally, striking a final blow to the old ways and birthing a new era of regular updates and advanced SERP features, Google released Hummingbird in 2013.

This update focused more on enhancing the platform’s own products instead of penalizing sites using black-hat SEO tactics.

Google, for instance, factored “intent” into search queries. For the first time, the search engine could tell whether consumers were looking for products, information, services, or entertainment.

This change impacted how SEOs approached search engine optimization tasks. Instead of targeting keywords generally, they focused on those embodying “commercial intent” or the desire to buy.

SEO In The Modern Day – 2014 to 2021

In the following years, search engines refined their services with multiple updates designed to enhance the user experience and deliver high-quality content. These changes caused the SEO industry to skyrocket in value, gaining more customers every year.

While many of these updates were led by Google they have been mirrored across other engines such as Bing, Yahoo!, Yandex, and DuckDuckGo as the search engine industry as a whole has evolved.

SEO in the Modern Day

Featured Snippets Arrive – 2014

In 2014, Google introduced featured snippets. Here, search algorithms determined whether it was worth highlighting in-page text in the search results window to answer users’ questions directly for a specific search request.

Initially, SEOs worried it would detract from organic traffic since users could gather all the information they needed from SERPs. Google Developer Expert, Amit Agarwal, tweeted the following at the time:


However, his fears didn’t pan out in practice. Instead, answer-providing web pages saw an instant increase in organic traffic, leading SEOs to specialize in this task.

Mobile Updates – 2015

At the same time, the mobile internet revolution was transforming how people searched for content online. By 2016, one-third (31.16 percent) of global web traffic came from smartphones and tablets, growing to 54.8 percent by 2021. In the second quarter of 2022, the figure jumped again to an incredible 59.16 percent, prompting SEOs to offer more mobile optimization services, helping brands adjust their online posture to cater to this market.

During that time, Google announced it could be “rolling out the mobile-friendly update” which would boost the ranking of mobile-friendly pages on mobile search results.

In response, agencies began redesigning websites to make them more responsive – ensuring they are viewable and user-friendly on smartphones and tablets. They also began building mobile sitemaps, accelerated mobile pages, and creating content suitable for devices with smaller screens.

These forces combined, expanding the SEO industry to $65 billion. Soon after, talk began about the possibility it could eclipse traditional advertising.

More recently in 2020 Google announced mobile-first indexing, with Google’s crawling switching to a smartphone user-agent as its preferred Googlebot.

Google’s Infamous Fred Update arrives – 2017

2017 marked another milestone in the development of SEO. Google released its Fred algorithm as part of its broad core update to remove what it perceived as low-quality results. Websites could no longer get away with aggressive ad placement or “thin” content that failed to give users value. They had to provide something engaging and useful.


The changes this new patch brought were devastating to some sites. Many brands saw organic traffic fall by up to 90 percent due to poor-quality, unhelpful content. Fred penalized them hard for aggressive affiliate marketing, overwhelming pop-ups, deceptive ads, shoddy content, and poor link quality.

For those hardest-hit, Google’s head of Search Relations, John Mueller had some advice:


This tweet marked a sea-change in SEO. It was no longer merely technical, but clearly geared towards quality.

For many, “recovering from Fred” became an obsession. Brands that suffered after the update had to revisit their site structure and reduce ad layout. They also had to reassess their backlinks and content from the ground up to make it “valuable” in the eyes of Google’s ever-more sophisticated algorithms.

This work was technical, so firms called in the SEOs to rescue them. Agencies and freelancers painstakingly optimized branded sites for mobile, increasing sales once more.

COVID-19 Boosts The SEO Market Further – 2020

In 2020, COVID-19 changed search behavior yet again. Pandemic-related restrictions forced consumers to search for products online, leading to an even greater reliance on the internet.

Because people couldn’t visit a physical location, they increasingly relied on brands’ digital marketing presence – their visibility online – to find what they wanted. This trend led to a further boost in the SEO industry, spiking demand.

Consider the figures. Twenty-eight percent more consumers shopped online during 2021 than before the pandemic, with 67 percent saying they increased their internet purchases in that time.

Moreover, the total share of online spending rose from 10.3 percent in 2019 to 14.9 percent by the peak of COVID-19 infections. Consequently, agencies specializing in local SEO and consumer products saw massive increases in demand for their services.

Given these factors, it is clear why the SEO industry is growing at break-neck speed. At the last count, there were 35,220 search engine optimization agencies globally, all trying to help brands reach the top spot in Google search results.

Google Releases MUM – 2021

Google released its Multitask Unified Model (MUM) in May 2021, marking the platform’s next step toward becoming a purely semantic search engine. The update was the next innovation following its Bidirectional Encoder Representations from Transformers (BERT) released in 2018, a system that let Google better understand users’ search intentions. Unlike RankBrain, BERT did not need to analyze past queries to understand what users mean.

MUM was a refinement of this concept. The updated AI-based technology lets Google understand natural language and use multimodal data to answer complex search queries, including images, videos, and audio files.

Google Expands The Concept Of E-E-A-T – 2022

After E-A-T was originally introduced in 2016, in 2022, Google made substantial changes to its Quality Rater Guidelines (QRG). The update added another ‘E’ making the acronym E-E-A-T, which now stands for “experience,” “expertise,” “authoritativeness,” and “trustworthiness.” The purpose of E-E-A-T was to help Google provide the best possible results for its users, especially for topics that require a high level of expertise or have a significant impact on people’s lives, such as health, finance, or legal matters.

Critically, E-E-A-T was not a direct ranking factor. Instead, it assessed other signals, such as reviews or user behavior, to determine website quality, forcing SEOs to consider site experience as a whole.

SEO: A $100 Billion Industry In 2023 And Beyond

A Brief History of the $100 billion SEO Industry

Helpful Content Updates (HCU)

First rolling out in 2022 and with a hefty update in September of 2023, the Helpful Content Update (HCU) is indicative of the kind of updates we can expect from Google moving forward.

Further prioritizing the importance of helpful content not only by rewarding sites that demonstrate helpful content, but also by punishing those that don’t, these updates seek to promote helpful user-first content. The first inklings are there as to how Gogle will be treating AI content on a larger scale, with many of those sites being punished using AI in a widespread manner, but it is safe to say it isn’t just these sites being affected. Many independent sites have been hit by these updates which serve to add site-wide classifiers onto not just an individual page, but rather the site as a whole.

You can read our full post, linked above, for a deeper dive into these updates.

Where We Stand Now

The 2021 CMO Survey found that nearly 74 percent of businesses invest in SEO. Google accounts for over 93 percent of all global search engine use, and two hundred ranking factors determine how it ranks pages. Because of this complexity, experts predict the agency segment will grow by an astonishing $45 billion by 2025, and the freelancer segment will increase by 20 percent over the same time.

Nobody knows where the SEO industry will go from here. However, estimates suggest it is already worth over $100 billion in the U.S. alone. This figure is based on the growth rate of the industry as a whole as well as growth with various service providers (such as agencies and freelancers), and end-user industries, including professional services, IT services, e-commerce, hospitality, recreation, and real estate.

Research and Markets predict that the global SEO market will reach $122.11 billion by 2028, with growth rates varying across sectors. It foresees small and medium-sized enterprise SEO demand growing by 20.6 percent per year between 2021 and 2028, meaning it will more than double in that time frame.

Predictions are that growth in other segments will also be rapid. For instance, figures suggest growth rates of 18.6 percent for large enterprises, 18.4 percent for healthcare, 17,1 percent for IT and telecom, and 17.9 percent for retail and e-commerce. Even in North America, the most saturated and developed market, forecasters see demand growing 16.5 percent annually until 2028.

These forecasts should, of course, be taken with a grain of salt.

There are always many factors at play in the shaping of the SEO industry. One current example is the rise of AI as we wait to see how search engines flexing their AI muscle impacts SEO, starting with Bing’s ChatGPT integration and Google’s Bard.

The Future Of The SEO Industry

From our perspective, the SEO industry is far from dead. Every analysis predicts it will continue to grow over the coming years as brands look for professionals who can help them dominate search results.

Given its history, we expect innovations in the SEO spaces to continue apace. As search engine algorithms become more complex, SEO gets more challenging and the need for more expertise is required.

That’s backed up by Google itself. According to John Mueller, updates run continuously.


Over the coming years, artificial intelligence will likely change the game again. One adaptation SEO will need to consider is how answer engine optimization (AEO) grows in value, not only with Google but also with Bing and other search engines.

SEO will not be replaced, but it will need to evolve continuously as it focuses on providing users with helpful results for a wider variety of queries while ensuring these efforts are creating a return on investment for clients.

The fundamentals of SEO optimization, link building, and content creation will remain as important as they have been from the very start!

For brands, these developments mean continuing to work on SEO is essential. Companies need partners who understand the evolving landscape and can help them respond to it fast.

Daniel Trick
Daniel Trick

Head of Content

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