It is the least spectacular job in a Google Ads account — and one of the most profitable: negative keywords. In B2B, the negative keyword list decides whether your budget reaches technical buyers or hobbyists, job applicants and students. A look at the practice.
Why B2B does not work without a negative keyword list
The fundamental problem of B2B search: buyers and private users use the same words. “Hydraulic cylinder”, “aluminium profile”, “conveyor belt” — the search query does not initially reveal whether there is a procurement for the production line behind it or a DIY project. Google serves your ad in both cases if you do not prevent it. You pay for the click in both cases.
The solution has two parts: tightly scoped keywords with clear purchase intent — and a systematically maintained list of the terms for which your ad should never appear.
Every euro spent on a search with no customer potential is missing twice over: as a paid click — and as a false learning signal for the automated bidding, which then goes on to buy more clicks of that kind.
The seven exclusion families in B2B
1. Private use
private, DIY, household, garden, hobby, for home use — the classics. On top of that, product-specific signals: anyone searching for “aluminium profile greenhouse” is not buying construction profiles in industrial quantities.
2. Do-it-yourself
build yourself, make yourself, DIY, tutorial, building plan, self-build. These searches want knowledge, not an offer — and there are plenty of them.
3. Used and bargain market
used, cheap, budget, second-hand, remaining stock, eBay, classified ads. Exception: you actually trade in used machinery — then this family belongs at the centre rather than on the negative keyword list.
4. Jobs and apprenticeship
job, position, salary, apprenticeship, internship, studies, further training. Particularly tricky, because job titles and product terms overlap — a “cutting machine operator” is not searching for a milled part.
5. Knowledge and definition searches
what is, definition, Wikipedia, how it works, difference, standard as a pure knowledge question. Valuable for content — expensive as a click.
6. Free-of-charge expectation
free, gratis, freeware, free sample, template. Anyone who does not want to pay anything rarely turns into an order.
7. Meanings from other industries
The most individual family: homonyms and neighbouring meanings of your technical terms. A “lift” is also a ski lift, a “press” is also a newspaper. These exclusions are found only by whoever reads the search terms report.
“The negative keyword list is not tidying up — it is audience definition with a reversed sign.”
From one-off setup to a system
A starter list with the families above belongs at account level, so that it applies to all campaigns — explicitly including Performance Max, which for a long time eluded classic keyword exclusions; by now negatives can also be maintained directly at PMax campaign level. The real value comes afterwards: in the monthly ritual with the search terms report. That is where it shows what your ads actually appeared for — and every out-of-industry search moves into the list. After three or four months of this maintenance, wasted reach drops measurably, and the automated bidding learns on a clean data set. Well-maintained accounts reach several hundred exclusions this way — and from then on every single one works for you for free.
- Does a negative keyword list exist at account level — with more than 50 terms?
- Are all seven exclusion families represented?
- When was the search terms report last reviewed?
- Are new findings systematically transferred into the list?
- Does the list also apply to your PMax campaigns?
Two or more “no”s? Then your budget is currently funding searches that will never become customers.