The immediate answer is no, you cannot have a product seen in a foreign country patented if the invention underlining the product – and which would be the subject-matter of the patent – is achievable in the product you saw.
In the first place, because the invention that is underlining the product is not a creation of your mind, of your inventor, or made by an employee from your company in the course of his or her employment contract or made by your order and in these circumstances, you are not entitled to the right in the patent, and thus any possible patent granted would be subject to cancellation, and
you would be committing a criminal unlawful act, of bad faith if you successfully got the patent granted;
In the second place, if you have seen the product abroad it means that the invention has already been disclosed and therefore does not meet one of the essential requirements for grant of a patent which is novelty, i.e., the corresponding invention already belongs to the state-of-the-art which is everything, inside or outside the country, made available to the public prior to the filing date of the patent application, by means of description, use or in any other way, it means also that, even if the patent would be granted, due to failure to detect the invention of the product you had seen as a result of the search conducted during the application procedure, such a patent would be null, and subject to declaration of cancellation at any time.
But, in case I change the invention so that such change may per se be considered an invention involving novelty, inventive step, and industrial applicability?
In that case, the new invention would be patentable!
28 May 2021