How Doorway Spam Gets Indexed in Google via LinkedIn Pages
Google search results are indexing LinkedIn pages with names of online casinos, bookmakers, and other gambling-related queries targeting various GEOs. This looks like a technical glitch, but behind it lies a doorway spam scheme that exploits dynamic URL routing.
In this piece, we break down how the scheme works, why Google indexes these pages, and what role LinkedIn's domain authority and spam-fighting mechanisms play in all of this.
How doorway spam works via dynamic routing
Large platforms and marketplaces commonly use dynamic URL routing. It allows pages with different addresses to be generated without a separate template for each one — a standard architectural feature of modern websites.
Abusers exploit the same mechanism differently. They mass-generate URLs using high-volume search queries — generic gambling keywords, casino and bookmaker names targeting different countries. If a search crawler receives a page it can crawl and index, that page may eventually appear in search results.
In LinkedIn's case, webmasters exploit the platform's routing features and domain authority to rank at the top of Google's search results. That's why LinkedIn pages with gambling queries can appear in search results.
The primary goal of this scheme is to capture organic traffic. A third-party domain is displayed in the snippet, and the operators are counting on users to copy it or type it manually into the address bar.
Why Google indexes spam
Google defines doorway abuse as creating pages to rank for similar queries that redirect users to a different destination. Among the examples cited by the company are mass creation of pages targeting cities and regions, generation of near-identical URLs, and intermediate pages before redirecting to another resource. The LinkedIn case fits this definition — only the keywords and GEOs change, while the page itself carries no standalone value.
The presence of such pages in search results does not mean Google considers them compliant. Spam detection is handled by SpamBrain — a system that operates continuously and analyzes billions of pages. Based on available data, the lag between spam appearing and algorithmic response ranges from a few days to several weeks, and in some cases longer.
LinkedIn's domain authority affects indexation speed. The domain is crawled regularly and quickly by search bots, and its high trust level allows new URLs to enter the index before the system has accumulated enough signals to evaluate them.
According to data from Sucuri, in 2024, 19% of the more than 422,000 analyzed sites with SEO spam contained gambling spam. In 2023, doorway pages accounted for 53.5% of all SEO spam cases. The scheme remains one of the most widespread among black-hat SEO operators.
The role of accelerated indexing services
Mass URL generation alone does not guarantee a fast appearance in search. To cut down on waiting time, accelerated indexing services exist — they notify Google directly about new pages via the Google Indexing API or IndexNow, rather than waiting for a search crawler to discover them on its own.
Services like 2index Ninja do not guarantee indexation and do not influence Google's algorithms — the decision remains with the search engine. But for a campaign running thousands of URLs, even a slight speed boost increases the number of pages that make it into search results before being removed.
Notably, the market for such services is not always transparent: the 2index Ninja promotional thread on BlackHatWorld was at one point closed following accusations of self-upvoting with fake accounts.
How effective is the spam scheme?
Directly comparing this scheme to classic doorway pages isn't quite accurate. With traditional doorways, a single click on a search result link is enough, whereas here the user needs to notice a third-party domain in the snippet, type it manually into the address bar, and navigate to the target resource. Each additional step filters out part of the audience, so the conversion rate is likely low.
We also found no real-world case studies or reports in the public domain showing how much this scheme actually generates in revenue.
But volume makes up for it. If spammers generate thousands of URLs targeting different brands, queries, and GEOs, even a small percentage of users completing the desired action produces a steady stream of leads. The calculation isn't based on the conversion rate of a single page — it's based on scale. The more URLs manage to get indexed before removal, the greater the chances of capturing traffic.
Conclusion
The LinkedIn scheme shows that Google can still be manipulated through trusted sources. LinkedIn's authoritative domain shortens the indexation time for new URLs, which is why similar schemes will keep emerging as long as the speed of their generation outpaces the speed of abuse detection.
