Some of our PPC clients have asked us which products are forbidden on Google Adwords. We have put together a list of must not advertise on Google and we suspect the list is pretty much the same for yahoo and Bing.

 Prohibited on Adwords

•  Drugs & Drug Paraphernalia
No selling weed, crack, meth, magic mushrooms, LSD, or any other mind-bending substances via PPC. You also can't sell bongs, glass pipes, and other getting high accessories... except for black lights, those are still ok.
•  Fake Documents
No fake driver's licenses, social security cards, diplomas, immigration papers, etc.
•  Steroids
•  Hate Groups
No hate groups, anti certain ethnic or religious groups, or groups that encourage violence against certain peoples
•  Counterfeit Designer Goods
No fake purses, jeans, leather goods, shirts, shoes, etc.
•  Prostitution
You really shouldn't bother trying with this one, that's what Craigslist is for... and it's free!
•  Gambling
No promotion of casinos or online gambling is permitted. You also can't promote sports books, lotteries, bingo, poker, gambling software, gambling tutorials, gambling eBooks, gambling affiliate sites, and even play for fun gambling sites.
•  Porn (sometimes)
This one is tricky; you can promote porn with Adwords. However there are a lot of off limits areas and you have to be very careful with your keyword strategy. You must stick with very specific queries that would only bring up adult results, and I would recommend phrase and exact matches here.
So what porn topics are banned? Anything to do with kids, teen pornography (even if the models are 18+ and the site is legal), anything denoting youth (school girl, etc), and non-consensual material or implied non-consensual material. I'm going to guess there's more that's banned that Google would prefer to not spell out.
•  Certain Weapons
Guns, bullets, parts of guns, switchblades, butterfly knives, and brass knuckles are a no-go. You can however promote more utilitarian knives like hunting knives and pocket knives.
•  Tobacco
Cigarettes, pipe tobacco, chewing tobacco, snus, cigars, and anything else full of nicotine that will make you smell bad and slowly kill you is prohibited.
•  Alcohol (except wine and champagne)
No beer, no hard alcohol, but wine and champagne is cool (weird I know).
•  Fireworks
If it is supposed to explode on purpose you can't promote it. In all fairness you can't really ship fireworks anyways; the post office gets a little skittish about explosive packages
•  Academic Cheating Services
This includes test taking services, paper writing services, and anything else that is academically dishonest
•  Drug Test Cheating Services
You can't sell "cleansing" teas or your little brother's clean urine with Adwords, sorry.
•  Illegal Traffic Devices
Radar jammers, plate blockers and traffic signal changers are all prohibited. Radar detectors seem to be ok however.
•  Miracle Cures
This doesn't cover miracle weight loss pills so much as a magic pill that may virtually cure AIDS and Cancer. While we're talking drugs and pills, prescription drugs are allowed -if- you are an Adwords approved pharmacy.
•  Scams, Phishing, Data entry affiliate sites, e-Gold, Dialers
If it's a known scam do yourself a favor and don't waste your time.
•  Bulk Marketing (E-mail Spam) Products
If you have a great e-mail list of thousands of e-mails you scraped from sites around the web you can't promote with Adwords.
•  Hacking & Cracking
You can't promote sites that teach you to illegally access software, servers, websites, cell phones, unlock copyright protection, descramble cable, and anything else illegal and hacker-y. You can promote hacker skills if they are for white hat defense purposes.
•  Automated Ad Clicking
Adwords rule number 1, don't mess with Google's wallet! Automated ad clicking is a good way to get your Adwords and Adsense accounts shut down in a hurry%u2026 oh and they have a word for this - fraud
•  Made For Adsense (MFA) Sites
Honestly I'm not sure how enforceable this one is, but it's on the books for good measure.
•  Copyrighted Material You Don't Own
Adwords is not the place to try and sell your pirated DVD collections
•  Webmaster Guidelines Violations
Don't openly promote with a Google service services to screw with Google, not smart my friend.