Domain owners are informed by a dubious company that there is interest in domains with the same name and that these have to be registered immediately.
An alleged domain name registry sends an email to the owner of a .ch domain. It claims that it has received a request to register the same .ch domain name under .net, .com, .biz or some other ending. The fraudsters now offer to register these domains. However, the prices are massively inflated and it is doubtful whether the domains will actually be registered after payment.