UKOKE Cordless Electric Power Hedge Trimmer with Dual-Action Blade w/ Battery & Charger $58.31 + Free shipping

If these smaller brands, off brands would design to use the more common Ryobi, DeWalt, Milwaukee, etc. batteries that the majority of portable tool users are already invested in, they would sell a lot more.

True, pretty sure they would be obliterated in patent infringement claims. IANAL but I think I heard of court orders to halt sales for infringement. If the manufacturer keeps selling they have to pay damages in excess of whatever the royalties would be if they lose in court. In a case like this where the patent holder does not want the product sold it would probably be several times whatever revenue it produced, let alone profit, along with a recall and destruction of the product.

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If they accidentally fit, or were designed with a snap off piece that then being modified, was 'discovered' to work as some of the more complicated mods out there, I not am seeing the problem. And then of course, there are the plethora of adapters being sold that nobody is going after. It is possible that the main players see it as selling more of their batteries, but probably would not object if the ambulance chasers could extract more profits.

Patent infringement is patent infringement regardless if it's accidental or not.

They could never, ever, advertise or hint, at something like a easy mod to use patented batteries from another companies system. Much less chance anyone will pick one of these up from another system without knowing that. This is all moot anyway. Yes they make money off of the tool, but batteries are far more profitable. To help think razors or inkjet printers. Both make the majority of their money the blades and ink, not the core product itself.

Major companies don't want to litigate to protect their brands, especially against small companies that have $0 on the books to actually pay the attorney fees let alone damages. Just look at the name! Once UKOKE is out of business for some patent infringement, the same tools will come out under MEKOKE or SKREWDAWELT etc. Just because you are awarded a trillion dollars in court does not mean you will see a penny off it, or are off the hook on millions in attorney fees.

Adaptors get cease and desists, then lawsuits if things go on. The problem is for every cease and desist there are probably 100 other accounts ready to go and sell. People fall for adapters being touted as dangerous, which they are to an extent. https://www.powertoolinstitute.co...dapter.asp [powertoolinstitute.com] Who the heck is charging with an adapter? Normally you are really into one brand but need to convert for a single tool from another brand. https://www.festoolownersgroup.co...-adaptors/ [festoolownersgroup.com] Here is a good discussion, but basically people don't want to risk their good tools. I don't get people wanting to convert from Ryobi to something else, but I get it the other way around. Dewalt, and the top tiers like them don't make choke products like Ryobi. I personally have no concern using a Dewalt battery with an adapter in a low draw Ryobi light or fan.

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And yet, everyone seems to be reproducing batteries that fit whatever, or adapters to fit whatever.

I spent a little time chasing down patents and the fact is, Milwaukee, a subsidiary of China based Techtronic Industries owns the patents for lithium ion technology used in tools... (7,554,290; 7,944,173; 7,999,510) and has already sued [jlconline.com] most of the players, or settled out of court like Makita did. Apparently, UKOKE and others are paying a royalty, or and possible, a subsidiary of Techtronic.

The patents for holding a battery have long ran out, but I would agree that anyone can file a lawsuit against anyone, where the conglomerates know the small player cannot afford the lengthy litigation costs.