well first thing first, patent, and intellectual property is two different entity altogether. Anyone is entitled to his/her own right to their created intellectual property, say writing, painting, photos, but industrial, technical, and engineering design require patent and patent law is different from region to region and country to country. One thing though, principle is that patent cannot be granted to any ( too ) generic design nor one that's already present. Trademark is somewhat similar to a patent but a ( usually ) graphic design ( itself an intellectual property ) registered to represent a business entity or physical product ..
By that account , trademark can only be observed unless its been registered and not previously appearing on the market. The classic example recently must be the AMD Ryzen CPU, which AMD initially called it Zen, but of course the word Zen is too generic and they cannot expect to trademark it nor enforce it either even if registered. That's also why Apple must refer themselves as APPLE COMPUTER, not just Apple.
The said Q regarding the 601 then is a matter of design cue / element . Well ink window, sorry this cannot be patented as its a generic feature and certainly not Parkers only. The shape of the pen can be argued for but again unless this had been registered in China and having a valid patent its not upheldable. And of course its not and even if Parker would want to patent it it wold not hold going through the patent office application ( since too many other brand and model had this industrial design already both Chinese and abroad ). In fact that is the case with the P51 having so many copies even in countries that recognize US Patent like all the many Italian pens of this shape in the 50's; my understanding of the history is that Parker also themselves had no interest in enforcing that either.
The Arrow clip, now that's the interesting part. I do agree in the broad and sane term its absolutely a plagiarism in play. But the legal side is by the time Parker officially enter the PRC market and ( if they ever do ) register arrow clip as trademark, the others ( Hero, Wing Sung and numerous others ) had already been using the arrow clip for decades, effectively meaning that this arrow clip design was no longer unique. So by the principle Parker cannot actually enforce the trademarking the clip and that's also why many of those vintage pens got a different clip on their export version because those are going to market where the trademark is registered and enforced. A simple fact is that before the 80's PRC and the world are separate on these matters and anything prior to that time, one cannot realistically expect it backtracked. This same actually apply to many Indian pen which also use the arrow clip.
Sure personally I am absolute certain that this is no less a copy alright but this is pretty common in industrial design and products. Few products are actually uniquely new. Like other had said before even Parker are copying , their Duofold Centennial is no more a modern one styled copy from Waterman's early flat top .. from a consumer POV so long the Mfr do not try to post it as a Parker, and come clean saying its a copy and a Wing Sung I am OK with it. The business themselves can care about the actual trademark, etc etc .. its theirs .. and as for retail sites like eBay, Amazon, well they are no different than good old brick and mortar sop regarding this. Do they sell these posted as a Parker 51 Vacumatic; well they do not so its back to the same Q and issue with the business in concern.
Edited by Mech-for-i, 17 January 2018 - 08:11.