
Key takeaways
- WebmasterWorld members were tracking ranking shifts in an Update Bourbon thread by 20 May 2005.
- A Google employee posting as GoogleGuy described Bourbon as about 3.5 search quality improvements.
- GoogleGuy said the changes would roll out in stages over the following week or so.
- Google gave no completion date and never said what each of the improvements changed.
- Industry reports linked Bourbon to duplicate content and canonical URL handling, a claim Google never confirmed.
What Google changed
Google never published a blog post about Bourbon, but it did acknowledge the update. In early June 2005, a Google employee who posted on WebmasterWorld as GoogleGuy described it in detail. John Battelle quoted him on 1 June 2005: “Bourbon includes something like 3.5 improvements in search quality, and I believe that only a couple are out so far.”
GoogleGuy did not say what each improvement did. A week later, as Search Engine Roundtable reported, he said a binary push had gone out with “hooks for the last part of Bourbon,” alongside reinclusions and responses to spam complaints.
Google never named it; Bourbon is a name the SEO industry adopted, from the WebmasterWorld threads that tracked the update.
When it rolled out
Google stated no start date. WebmasterWorld members were already tracking shifts in the Update Bourbon thread on 20 May 2005, so this page uses that date; the exact day is approximate. On 1 June, GoogleGuy said the last major change “should roll out over the next week or so,” with minor changes after that. Google gave no completion date.
What is known about its impact
Google published no impact figures. GoogleGuy’s advice was to take a break from checking rankings for several days while the stages rolled out. Webmasters at the time speculated that Bourbon changed how Google handled duplicate content and non-canonical URLs, such as www and non-www versions of the same page. Google never confirmed that, so treat it as industry theory.
What site owners should do
Bourbon itself is history. If the duplicate URL theories apply to your site, Google’s current canonicalization guidance is the place to start. It says canonicalization is “the process of selecting the representative” URL for duplicate content, and that some duplicate content is normal and not a spam violation.
- Pick one preferred version of each URL and redirect or canonicalize the others to it.
- Keep internal links pointing at the preferred URL.
- Focus on content made for people, as Google’s helpful content guidance recommends.
How to check whether it affected you
This is a historical question. Search Console keeps 16 months of data and did not exist in 2005, so the only evidence would be server logs or analytics archives from May and June 2005. For anything recent, the Google Algorithm Updates timeline lists every update with its dates, so you can check what rolled out when.
Related updates
- The Austin update was the previous widely tracked ranking change, in 2004.
- The Jagger update followed in October 2005, again announced through forum and blog posts.
- The Big Daddy update later brought Google’s own promise of improved canonicalization.
The evidence
- Type
- other update
- Started
- 20 May 2005
- Completed
- Not stated by Google
- Confirmed by
- Google statement
- Name
- Coined by the SEO industry
Sources
- 1.Last Wave of Bourbon Google Updates - Search Engine Roundtable, June 7, 2005Primary
- 2.Google Update "Bourbon" - John Battelle's Search Blog, June 1, 2005
- 3.Google Update Bourbon - Part 1 - WebmasterWorld, May 20, 2005
- 4.What is URL canonicalization - Google Search CentralPrimary
- 5.Creating helpful, reliable, people-first content - Google Search CentralPrimary
Frequently asked questions
Did Google confirm the Bourbon update?
Yes, informally. A Google employee posting as GoogleGuy on WebmasterWorld described the update and its staged rollout, and Search Engine Roundtable and John Battelle reported his posts. Google published no blog post about it.
Why is it called the Bourbon update?
Bourbon is a name the SEO industry adopted; it was the name of the WebmasterWorld threads that tracked the update. Google did not name it.
What did the Bourbon update change?
Google did not say in detail. GoogleGuy described it as something like 3.5 improvements in search quality. Webmasters speculated about duplicate content and canonical URLs, but Google never confirmed those theories.
When did the Bourbon update happen?
Webmasters were tracking it on WebmasterWorld by 20 May 2005, and GoogleGuy said on 1 June that the last major change would roll out over the next week or so. The exact start day is approximate.
About the author

Founder, UpgradIQ FZC LLC
Adam Hafez works on technical SEO and search measurement: how pages get crawled, indexed, ranked and now quoted by answer engines. He founded UpgradIQ, which reads Google Search Console and GA4 to tie ranking movement back to the changes that caused it. He publishes what the data supports and states the limits of it.
- Technical SEO
- Search Console and GA4 measurement
- Answer engine optimization
- Structured data
The briefing
Only what actually changed in search, delivered in full by RSS, Atom or JSON feed.
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