Why you need a multi-engine SEO strategy

Multi-engine SEO means optimising your online presence for more than one search and discovery ecosystem (traditional search engines, AI systems and social/community platforms), rather than treating Google as the only route to organic visibility.

Businesses solely optimising for Google may be missing out on other ways people discover businesses and products online. AI search experiences such as Microsoft Copilot and ChatGPT are becoming part of how people find answers and discover businesses. This means considering where your customers are actually searching and how your website can be discovered across these different platforms.

This article explores the case for a multi-engine SEO strategy with a particular focus on traditional search and AI-powered search.

Should I optimise my website just for Google?

Bing’s web index matters for AI SEO – but it isn’t the whole picture

Traditional search indexing vs AI Search grounding

What do I need to do to improve my visibility on Bing and Copilot?

What do I need to do to get my site included in ChatGPT Search?

How to measure ChatGPT mentions with Google Analytics

Summary

Most of your SEO efforts should not be just for Google, because doing so excludes users who exclusively search on other platforms and/or miss opportunities to appear in other search and AI discovery experiences. If you’ve been wondering why Copilot or ChatGPT has not yet surfaced your website, read on.

Most businesses spend all their SEO effort on Google, as it has often provided the highest volume of organic traffic accounting for around 91% worldwide search-engine market share as of Aug 2026 (1). While Google is an important channel for most businesses, it doesn’t mean it should be the only search platform you consider. The most appropriate mix depends on your audience, industry and business goals. Moreover, if your audience uses multiple discovery platforms or solely uses AI platforms instead of traditional search, a broader search strategy can reduce your dependence on a single source of organic visibility. (2)

The second largest search engine is Microsoft Bing which accounts for around 4.5% market share globally across all devices (1). It might not sound like a lot but is it still worth having your website on Bing? Yes, here’s why.

Here is the part nobody mentions: Microsoft Copilot uses Bing for web search and for grounding its responses in web results.

How it works: First, Copilot generates a query and sends it to Bing. Bing’s results are then used to ground the response (3).
However, it’s important not to treat Bing as the single index behind every AI search engine. Different search/AI ecosystems have different discovery mechanisms.
ChatGPT, for example, has its own OAI-SearchBot crawler, which OpenAI uses to surface websites in ChatGPT search results. OpenAI recommends allowing OAI-SearchBot to crawl your website if you want your pages to be discoverable and cited in ChatGPT search (How to be discoverable in ChatGPT). (4)

The AI cannot cite what it cannot retrieve, even if your page has the best answer on the internet.

AI search systems retrieve and evaluate web information differently from how a human user interacts with a traditional search results page. There are fundamental differences in the way traditional search and AI search work by assessing content in different ways.

Different search/AI ecosystems have different discovery mechanisms. Microsoft explicitly explains the major difference between a page being indexed and a page being ‘groundable’.

Traditional search index addresses: ‘which pages should a user visit’ to surface as many relevant options as possible and let the user choose. This is designed for humans who can scan a results page and skip the results that don’t fit in real time.

In AI search, content needs to provide clear, supportable information that retrieval and grounding systems can use as ‘evidence’ when constructing an answer.

Grounding involves determining whether information can responsibly support an AI answer, including factors such as:

• Factual fidelity
• Freshness
• Source attribution
• Coverage
• Conflicting sources
• The quality of retrievable information

AI search grounding looks at ‘what information can an AI system responsibly use to construct an answer and which source should it attribute?’ the system is no longer just pointing to information, it is using it. (5)

The goal shifts towards retrieving the best information it can find to generate its own reliable, verifiable answer, rather than copying text over directly. The other contrasting feature to be aware of is when an AI system presents an answer, multiple sources might collapse into a single statement and errors can compound across reasoning steps.

No gatekeeping: One useful technical tool for keeping Bing’s index up to date is IndexNow. IndexNow lets websites notify participating search engines, including Bing, when URLs are added, updated or deleted. This can help search engines discover important changes faster than relying solely on their normal crawling schedules. Don’t assume that an IndexNow submission guarantees immediate indexing.

1. Set up Bing Webmaster Tools. You can quickly import existing data straight from Google Search Console.
2. Open “Site Explorer” to view your Bing-indexed pages. If important pages are missing from Bing’s index, it’s a useful indication that it’s worth investigating your Bing and Microsoft AI visibility.
3. Switch on IndexNow. It’s available through the IndexNow WordPress plugin and is also supported by several SEO plugins, including Rank Math, Yoast, AIOSEO and SEOPress. Some platforms and services also provide built-in support.
4. Check your robots.txt for a bingbot disallow(rules blocking Bingbot’s crawler). Also check that important pages aren’t blocked by noindex directives.
   For example*:

5. Publish something. Later use Bing Webmaster Tools’ URL Inspection or search Bing using the URL to check whether the page has been discovered and indexed.
To ensure your content is indexable and “groundable” for generative engines, Microsoft recommends specific actions in its Bing Webmaster Guidelines.

To help your website appear in ChatGPT Search, allow OAI-SearchBot to crawl your site.
OAI-SearchBot is OpenAI’s crawler for surfacing websites in ChatGPT Search. If you block it, your site won’t be shown in ChatGPT search answers (4).

Check your robots.txt for an OAI-SearchBot disallow (rules blocking OpenAI’s crawler).

For example*:

You also need to make sure your hosting/CDN/security system isn’t blocking the crawler. OpenAI specifically mentions firewalls, bot protection, CAPTCHAs and rate limiting as possible causes of failed crawling.

After changing your robots.txt, allow time for OpenAI’s systems to update; OpenAI says this can take around 24 hours. (6)

*This is an example of explicitly allowing it – you don’t necessarily need to put an Allow: / into your robots.txt if you have no Disallow rule affecting OAI-SearchBot or bingbot.

OpenAI says that websites allowing OAI-SearchBot can track referrals from ChatGPT in analytics.

ChatGPT automatically adds utm_source=chatgpt.com to referral URLs, allowing you to identify ChatGPT traffic in analytics.

What to do: In GA4, Check Acquisition > Traffic acquisition > Session source
and identify ChatGPT referrals.

Google is still the predominant search engine for handling most organic searches globally. AI search experiences have become a major evolution of search.
Bing visibility has become strategically important for AI-powered search, particularly for Microsoft Copilot which uses Bing for web search and grounding. ChatGPT has its own search infrastructure, including OAI-SearchBot, which OpenAI uses to surface websites in ChatGPT Search.

Traditional search and AI search share similar foundations in crawling, retrieval and understanding but are optimised for different outcomes.
Traditional search indexing optimises for relevance. It was designed to help direct users what to read – a human user can then scan, choose answers or skip results that don’t fit.

AI search systems need to assess the strength of ‘evidence’. This can involve factors such as factual accuracy, freshness, source attribution and the quality of retrievable information. While also taking into account the possibility there may be statement errors that can still appear across LLM reasoning (where sources conflict or info is incomplete).

This reasoning makes it more important than ever to adapt to a multi-engine optimisation strategy; to help mitigate impact of organic traffic vulnerabilities from algorithmic volatility, differences in how audiences search, and the increasing number of zero-click searches answered directly within AI-powered search experiences.

For Bing and Copilot, businesses can create a Bing Webmaster Tools account, check their site’s indexation, and implement IndexNow to help participating search engines discover new and updated URLs more quickly.

For ChatGPT Search, businesses should make sure OAI-SearchBot is allowed to crawl their website. ChatGPT referrals can also be measured in analytics.

You don’t necessarily have to optimise for all traditional search engines and AI systems. The strategy should depend on where your target customers actually search.

If you’re looking for further advice or need help navigating the complex search landscape of SEO and GEO, we’re here to help with SEO strategy packages and custom website design informed by data that’s optimised to convert.

1. Search Engine Market Share Worldwide – Stat Counter

2. What are the 5 top search engines? [August 2026 Update] – WP SEO AI

3. How web search works in Microsoft Copilot Chat and agents – Microsoft

4. Publishers and Developers – FAQ – OpenAI

5. Evolving role of the index: From ranking pages to supporting answers – OpenAI

6. Overview of OpenAI Crawlers – OpenAI Developers