Rules and ethics
Part of Before you plan content, the keyword research rules and ethics to follow
Before you launch ads, check keyword research advertising rules
A checklist for checking keyword research advertising rules in England, covering CAP, ICO and FTC enforcement plus a worked advertising budget example.
What to take away
- The most common mistake is treating keyword research as an editorial task, then handing the same keyword list to a paid ads team without checking the claims it implies. Advertising rules bite at publication, not at data collection.
- In England, the CAP Code applies to ads in UK media, and ASA rulings show how claims built from keyword data have been judged. Any keyword that feeds ad copy sits inside that code.
- The ICO's direct marketing guidance governs how you collect and use personal data for targeting and follow-up. Keyword research that touches customer lists or lead forms falls under it.
- FTC warning letters show that misleading marketing claims attract enforcement beyond the UK, so keep evidence for every claim a keyword implies.
The rules that catch keyword research
Where keyword data becomes an advertising claim
Keyword research rarely breaks the law by itself. It breaks it when the phrases you choose become headlines, bids or landing page promises. Under the CAP Code, ads must be legal, decent, honest and truthful, and the ASA enforces this through published rulings on claims that could not be substantiated.
Three UK rules do most of the work here. The CAP Code — formally the UK Code of Non-broadcast Advertising and Direct & Promotional Marketing — carries the standards the ASA enforces, and its Section 3 rules cover misleading claims (3.1), substantiation (3.7), price claims (3.17 to 3.22) and comparisons (3.33 to 3.35). The Consumer Protection from Unfair Trading Regulations 2008 make misleading commercial practices a criminal offence, and the Business Protection from Misleading Marketing Regulations 2008 apply to ads aimed at other businesses. Where the keyword list touches personal data, the UK GDPR and the Privacy and Electronic Communications Regulations 2003 (PECR) apply as well.
Keyword to advertising claim
- Keyword chosen for the list
- Becomes headline, bid or promise
- CAP Code: legal, decent, honest, truthful
- ASA checks substantiation
- Unsubstantiated claim ruled misleading
If your keyword list includes "cheapest" or "guaranteed", you are choosing a claim, not a search term. Keep the source for each claim with the keyword record, because the ASA rulings database shows how often the wording of a claim decides the outcome, not its intent.
Data collection behind the keyword list
Many keyword projects collect personal data, even indirectly. Search console exports, CRM queries and lead form responses all contain identifiers. The ICO's step-by-step guide to direct marketing for your small business sets out the consent and opt-out workflow you need before using that data for targeting.
Check the lawful basis before the campaign launches, not after a complaint arrives. Personal data used for keyword research, targeting or follow-up sits under the UK GDPR and the Privacy and Electronic Communications Regulations 2003 (PECR). The ICO's guidance on direct marketing sets out the consent wording, the opt-out you must offer and the records you should keep.
A pre-launch checklist for ad keywords
Step one: map each keyword to a claim
For every keyword you plan to bid on, write the claim it implies if used verbatim in an ad. If that claim needs evidence, attach the evidence before the campaign goes live.
Pre-launch keyword ad checklist
- Map each keyword to its implied claim
- Attach evidence before campaign goes live
- Rewrite or drop keywords without evidence
- Confirm lawful basis for every audience list
- Check consent wording and date
- Record legitimate interests balancing test
A keyword like "same day service" needs a delivery record, and "award winning" needs the award. Where no evidence exists, rewrite the keyword or drop it from the paid list.
Step two: check the targeting data
Confirm the lawful basis for every list used to build audiences. If consent is the basis, check the wording and the date. If legitimate interests is the basis, record the balancing test. Use the ICO guide above as a tick list, not a reference document.
Step three: read the rule that governs each claim
For every claim you keep, open the CAP Code rule that covers it: misleading claims under 3.1, substantiation under 3.7, price claims under 3.17 to 3.22 and comparisons under 3.33 to 3.35. If your wording falls short of the rule, rewrite the ad copy before the campaign goes live, not after a complaint lands.
Step four: check price and comparison keywords
Keywords such as "cheap", "cheapest" or "best value" are price claims, so the figure in the ad must be the price the customer actually pays. A comparison with a named competitor must rest on evidence a third party could check, and it must be like for like.
Step five: file the evidence with the keyword
Store the keyword, the claim it implies, the evidence and the date the evidence was checked alongside the keyword list. Keep the record while the ad runs and for a reasonable period after it stops, so you can answer a complaint from the ASA or a query from Trading Standards.
Enforcement and a worked example
What enforcement looks like
The ASA publishes rulings on ads that breached the code, and the pattern is consistent: unsubstantiated claims, misleading comparisons and prices that were not genuine. In the UK, the Consumer Protection from Unfair Trading Regulations 2008 make misleading commercial practices a criminal offence, enforced by the Competition and Markets Authority and by local authority Trading Standards, while the Business Protection from Misleading Marketing Regulations 2008 cover ads aimed at other businesses. The FTC's warning letters show the same pattern in the United States, which matters if your ads run across markets. No regulator needs intent, only an ad that a reasonable consumer would find misleading.
A worked example
Suppose a team pays £400 a month for keyword research tools and £600 a month for paid search, so £1,000 a month in total. If one keyword drives a claim the ASA later upholds as misleading, the team must pull the ad and rewrite the landing page.
Rerunning the research, for example, could add £250 in internal time and £150 in new tool queries. The original £1,000 is spent, and the corrected campaign starts again. These figures are illustrative only, and individual cases need a qualified adviser.
Check the live CAP Code and the ICO's direct marketing guidance before you brief the ads team, and keep the evidence for any claim a keyword implies with the keyword record. Both are updated, so work from the current versions rather than a saved copy.
Common questions
Does keyword research need its own compliance sign-off?
Not as a separate process, but any keyword that becomes ad copy does. Treat the handover from research to paid media as the control point.
Which regulator covers keyword-driven ad claims in England?
The ASA enforces the CAP Code for ads in UK media. The ICO covers the data used for targeting and follow-up.
Do US warning letters matter to UK teams?
Only if the campaign runs in US markets. They are useful evidence of how misleading claims are treated elsewhere.
How long should we keep claim evidence?
Keep it for as long as the ad runs and for a reasonable period afterwards, so you can respond if a complaint is made.
