The Wright brothers were the original patent trolls and they held up US aviation for decades. https://en.wikipedia.org/wiki/Wright_brothers_patent_war They would file and stretch their patents to try and cover what others invented.
> The Wright brothers were the original patent trolls Edison was not only a patent troll, but was besieged by other patent trolls. He spent much of his career in court defending his patents and trying to overturn others.
Do you even know what a patent troll is? Edison actually invented many items that he patented and defended against infringers (and he trod on a few others patents).
Usually a patent troll has never registered a patent. He buys patent rights to any and all things he can get very cheaply, He then has all the claims assessed to see if there is a fragment that applies to any company that uses that technology - and writes a demand letter for infringement fees. They often ask for $10,000 to $25,000 and many companies who are faced with hiring lawyers and spending $500,000 in even a winning defence - choose to pay it. The trolls live on these fees. I could live well on one letter a month. The troll has low costs, a copy of Word on a computer abd a printer + postage and often send hundreds of letters a day.
Read this.