What is bl.uk_lddc_bot?
bl.uk_lddc_bot is operated by the British Library as part of their legal deposit web archiving program, which collects and preserves UK web content for the national archive. This bot crawls websites to fulfill the library's obligation under UK legal deposit legislation to archive online publications. Agent Analytics can track when it visits your website.
Category
Expected Behavior
bl.uk_lddc_bot returns on a cadence to capture full snapshots of your pages for the historical record. Expect complete page fetches rather than metadata checks, at a frequency that rises with your site's popularity and how often your content changes.
Overview
| Operated By | British Library |
| Expected To Follow Robots.txt | Yes |
| Insights Last Updated | July 6, 2026 |
Robots.txt Blocked Percentage
Country of Origin
Robots.txt Blocking Trend
As of July 6, 2026, 0% of top websites block bl.uk_lddc_bot in their robots.txt files.
Overall Archiver Traffic
As of July 6, 2026, 0.1% of all web traffic came from archivers.
This data reflects agent visits measured across thousands of websites using Agent Analytics, combined with daily scans of the world's top 1000 websites and their robots.txt files.
bl.uk_lddc_bot's User Agent
| User Agent | bl.uk_lddc_bot/3.4.0-20220727 (+https://www.bl.uk/legal-deposit-web-archiving) |
Access other known user agents and IP addresses using the Enterprise API.
How To Block bl.uk_lddc_bot
Add this rule to your robots.txt file to block bl.uk_lddc_bot from accessing your entire website. You can customize which pages are blocked by swapping out / for a different path.
User-agent: bl.uk_lddc_bot # https://knownagents.com/agents/bl-uk-lddc-bot
Disallow: /Frequently Asked Questions
Should I Block bl.uk_lddc_bot?
Almost never. bl.uk_lddc_bot preserves snapshots of your pages so the record survives redesigns, migrations, and dead links. Blocking only stops new captures. Snapshots that already exist stay public until you ask the archive itself to remove them. Almost none of the top websites we track have robots.txt rules for bl.uk_lddc_bot right now.
Does bl.uk_lddc_bot Respect Robots.txt?
Yes. bl.uk_lddc_bot is expected to honor robots.txt rules, so a disallow rule is the right first move. Automatic Robots.txt adds and maintains that rule for you, and Agent Analytics confirms bl.uk_lddc_bot actually honors it.
Does bl.uk_lddc_bot Access Private Content?
It archives only what any anonymous visitor can see. Anything public at crawl time can stay retrievable in bl.uk_lddc_bot's archive long after you take it down.
Why Is bl.uk_lddc_bot Visiting My Website?
bl.uk_lddc_bot is preserving your pages as part of the historical record. Visits recur on a schedule so the archive can capture how your content changes over time.
How Can I Tell if bl.uk_lddc_bot Is Visiting My Website?
Agent Analytics tracks bl.uk_lddc_bot visits in real time alongside every other known AI agent, crawler, and scraper. You can also check your server logs for requests whose user agent string contains "bl.uk_lddc_bot". Look for periodic full page captures that recur on a schedule. Keep in mind that bl.uk_lddc_bot doesn't publish a verification method, so any client can claim its user agent string and a log match is a hint rather than proof.