I was recently contacted for marketing PrimeXBT so I did a little web search and found this topic before jumping on-board. I was wondering and I asked Bitmex about the company number not being found on Seychelles online registry and got the following answer:
The information in our Terms of Service is up to date and correct.
I confirm that HDR Global Trading Limited was incorporated under the International Business Companies Act of 1994 with a company number of 148707.
Only local companies that were incorporated under the Companies Act of 1972 show up in that registry.
I know this is not contributing to the argument in either way at this point, and I don't know if it is really correct or not but in case anyone was wondering.
I would like to add that off-shore companies should only be preferred for services that cannot be obtained otherwise. In case of disputes, taking action would either be a legal dead-end or very expensive.