(edit: I see someone says you posted the letter as a pdf link and I missed it. And that you might be using their trademarks. Be very very very careful about trademarks: I often come on here to tell people not to fuck with trademarks if you do stuff like this as that's often the only case these companies have and it is so easy to avoid. I am tired though and have a meeting and am not going to read the pdf, especially as that will verge even more into the danger zone of me giving you legal advice. The rest of what I said here stands.)<p>I am not a lawyer. I deal in this area, but I have lawyers--lots of lawyers--and my primary recommendation is that if you work in this space you have a lawyer.<p>I am going to tell you something, though, about this cease and desist. From the perspective of it effectively being "advice", I encourage you to consider it a "this is the minimum level of damage they can do to you": I am not saying there aren't interesting things that I don't know off--that's like, why we have lawyers--that would <i>really</i> screw you. I also haven't analyzed your extension in any way to know anything about your situation other than what you wrote.<p>> Cease and desist developing, offering, or using software or programs with features developed, marketed, or intended for automating activity on LinkedIn’s website or app, scraping LinkedIn member data, or otherwise violating the LinkedIn User Agreement.<p>The user agreement is an agreement that has limited consideration and limited recourse. Typically, they can take their balls back and send you home (it's their court, so they don't have to leave), so if they want to they can terminate your account... it isn't <i>illegal</i> to violate the terms of even a well-accepted and carefully done contract (which terms of service ain't), but the recourses for such a limited consideration is also pretty limited, and they know this enough that it even says it in the agreement: they can terminate your account.<p>If this were me, I barely use LinkedIn. I haven't had a normal looking job in forever and I have no interest in getting one ever again. I don't care about my profile (despite updating it every decade or so) and I only check for new connections and messages once every year or so. I really only use the service for cyberstalking, and never understood why people care so much about it. If they wanted to terminate <i>my</i> account, well, "big whoop", right? I'd tell them to go pound sand. Hell: that user agreement--which they are really trying to make legit--seriously says you can terminate it at any time (in exchange for your account being terminated).<p>But maybe you like LinkedIn and need your account. If that's the case, you should cease and desist and maybe even try to apologize while pleading a lack of knowledge of what you were doing or why it was a problem. (But of course, if they then terminate your account, come back with a literal vengeance and refuse to deal with them until they give you back your account.) But like, just realize: you likely aren't coming out of this one with a LinkedIn account if you want to keep developing this extension. FWIW, I have definitely done stuff like this for years despite large companies with lawyers wishing they could stop me.<p>That said, you also might get sued. You can always get sued: that's how our legal system works. They might not have a case, and maybe you can get it thrown out, but that's a leap. You should have a lawyer, and they can advice you on the risks of that. But I can say: if you can't afford to sit around in court for a year arguing with them about this, you might be playing in the wrong league, as the court system in the United States requires you to be prepared at any time to pay to be in court and very much assumes anyone doing commercial activity has a lawyer.<p>Again: I am not a lawyer. For all I know, you are also violating the CFAA or a law I have never heard of. I have not seen your extension. You also only gave us one sentence of the letter verbatim and one other reference (to hiQ) summarized (edit: I missed the pdf link, per above). And I have a lawyer I would consult before responding, a lawyer I have not consulted today on your behalf: I am just a guy who is telling you "expect to lose your account" and "the account wouldn't have mattered to me and I wouldn't be afraid, as someone who has successfully done stuff like this for years and has multiple lawyers" (edit: but also as someone who is super anal about trademarks).