Is it legal to do this?

Here is the interesting thing. NO ONE would own those rights. I could take your trademark and use it. When you come after me as MYCOMPANY I'd go before the judge and show that your site said these are owed by MYCOMPANY LLC. I'll show the Judge that MYCOMPANY LLC didn't and still doesn't exist. Your case of trademark infringement would be thrown out as you'd have NO LEGAL STANDING in the case. The only people that could sue me would be MYCOMPANY LLC people. Since they don't exist I can do whatever I want with your trademarks. In fact I could go register that trademark if you don't have it registered under another name. NOW if that was the case I'd show you are committing fraud.