[codingdave]

Letters can be ignored. Lawsuits must be responded to. And that same 35K will be offered as a deal after they file, if they file. They are trying to save THEIR legal costs, not yours. Let them sue. Fight it in court. Hopefully win. Counter-sue for your legal fees. Booyah.

Note: IANAL, and any actual lawyer would be less flippant. But seriously... don't let attorneys bully you.

[CodeWriter23]

Armchair Lawyer here. I've successfully fended off letters like this by simply not responding to them at all. My silence (and the implied BIG middle finger therein) laid down the gauntlet that their only options are to hire their lawyers to file their case, or STFU.

[rlabrecque]

Doesn't the article say this patent has been successfully used in the past and thus there's likely precedence? :/

[CodeWriter23]

Yeah, 10 years ago. The anti-troll arsenal has grown extensively since then. Personally, I'd file for a USPTO patent review and try to take the patent away from them on the basis that it is neither novel nor innovative.