Every ad account quietly pays for clicks it never wanted: freebie hunters, job seekers, students, people shopping for the thing you do not sell. Negative keywords are how you stop, and generating them is keyword generation with the filter inverted.
Here is the launch list, the mining method, and the weekly loop that keeps the leaks sealed.
The leak you are paying for
Step 1: generate the junk on purpose
Run your paid seeds through the generator exactly as if researching content, then read the results with opposite eyes: every suggestion you would never want to pay for is a negative candidate.
"[Your product] free download", "[your service] jobs", "[your product] repair": the generator surfaces the real junk phrasings at scale, which beats guessing them one by one in the ads interface.
Step 2: apply the universal negative categories
Most wasted spend falls into six intent buckets. This is the modifier list read backwards: the same words that generate keywords for one business are negatives for another.
| Bucket | Negative candidates | Unless you... |
|---|---|---|
| Freebie hunters | free, freeware, torrent, crack, open source | Offer a free tier worth advertising |
| Job seekers | jobs, careers, salary, hiring, internship | Are recruiting |
| Learners | what is, course, tutorial, pdf, certification | Sell education |
| DIY researchers | diy, how to make, homemade, template | Sell materials or templates |
| Wrong condition | used, second hand, refurbished, rental, cheap | Sell those conditions |
| Adjacent products | repair, parts, accessories, alternatives | Sell those too |
The "unless" column is the whole skill. Negative lists are business-specific by definition, which is why copying someone's mega-list unedited blocks real buyers.
Step 3: mine the middles
The cursor trick works for junk too: "your product ___ price" and "best ___ [category]" middles expose competitor names, wrong models and adjacent products people wedge into your queries.
Competitor names deserve a deliberate decision rather than a default. Bidding on them is a strategy with real costs and occasional payoffs; accidentally matching them through broad match is just a leak.
Step 4: the search terms report loop
Everything above is the launch list. The permanent source is the search terms report: the actual queries that triggered your ads, with their costs attached.
Weekly for the first month, then monthly: open the report, sort by spend, and classify each unwanted query into a bucket. Add the negative at the level it belongs, shared list for universal junk, campaign level for specifics.
The report also pays a dividend nobody expects: it is a keyword generator for the other direction. Queries you happily paid for but never targeted are commercial keywords validated with your own money, ready for exact-match targeting and content.
Step 5: structure the lists
Keep one shared negative list for the universal buckets, applied account-wide, so every new campaign starts sealed. Keep campaign-level negatives for the specific: a campaign for the premium line negates the budget line's model names, and vice versa.
And remember negatives match literally: no synonym expansion, close variants only. The junk needs listing in its real phrasings, which is exactly what step 1 harvested.
The one-line takeaway: generate your niche's junk on purpose, bucket it with the universal categories minus your "unless" exceptions, and let the weekly search terms report grow the list with evidence. Negatives are the cheapest performance upgrade in PPC.