I think you know the answers to some of these questions so why ask? The hinge is pretty much necessary to make a more compact fold.The simple arc is quite strong and minimizes welding how it is done. Of course the hinge could have been put in a different place but without running a structural analysis on it I can’t say for sure. I dealt with a lot of these intellectual property issues and patents in a previous job. I personally don’t have much desire to revisit that time in my life when it relates to something I am not directly involved in.

Bottom line is sometimes you get a patent when you shouldn’t and sometimes you shouldn’t get one but you do anyway. I have no stake in this situation so I’ll let the relevant parties sort it out rather than be an armchair advocate (lawyer) here. If/when it all plays out then I’ll be more interested. As it is I like my Merc much better than my last Brompton. For me it is functionally better bike and I don’t give a darn if it looked like a Brompton or not. I was never that taken (actually NEVER taken) with the Brmoptons looks. About the only thing I really liked about it was its diminutive fold. The Merc substantially addressed most of my major issues with the Brompton and did it at a price that undercut Brompton’s less well equipped models. It could have been more expensive and I would still have bought it. Price wasn’t a factor for me; functionality was.

Keep in mind that bike designers have limited sizes and specs of equipment they can buy “off the shelf” so as to reduce costs and minimize building everything custom and in house. Then we’ll all complain about all the non-standard parts it uses, yada, yada, yada. The plus to the basic Brompton design is it is very simple. No complex folding bits like Birdy.