Blaze: actually, it is a violation . . .
• Yes, it is a violation and Kirbys lawyers care. That's why they sent me an official response.
• Putting a "kirby-branded" bag on a Hoover is totally unrelated. It doesn't matter what machine you put it on. What matters is that you reproduced another company's logo and then tried to pass off a replacement part as OEM when it's not.
• I contacted their legal dept. because I didn't want to screen print a bunch of bags, post the pics online, then have Kirby tell me to stop. I've worked in advertising, I respect trademarks and brands, so that's why I contacted them first.
• I know a couple of Kirby dealers who are interested in selling these bags. However, they'll lose their dealerships if they sell improperly branded Kirby replacement parts.
• You're right that there are all sorts of illegally sanctioned items, like Chevy doormats or T-Shirts, that use someone else's brand without permission. Lots of stuff flies under the radar. However, if you started making Chevy auto parts and put the Chevy logo on them, you'll definitely hear from GM's lawyers.
• Some companies are very aggressive about this. Monster Cable, the speaker wire company, is notorious for harassing anyone who uses the word "Monster." They once sued a mom and pop dry cleaning company called "Monster Dry Cleaning." Imagine what they would do to someone making replacement wires with the Monster logo?
The reason why vacuum cleaner companies put their logo on their bags is because it's the best way to protect their revenue for OEM replacement parts. They can't patent the actual bag, so they put their logo all over it. Copy that design with their logo and they can shut you down for a trademark violation, not a patent violation.
Maybe Tom Gasko can shed more light on this subject. I am sure he knows far more than I do about the history of brands going after bojack suppliers that put OEM logos on their parts.