I saw this posted on another board: " N-Assay pape

I saw this posted on another board: " N-Assay paper is in the hands of a major medical journal and sequester guidelines prevent mention of which journal, acceptance, or publication until after the fact of publication, which I understand to be common practice. He did say papers can only be submitted to one journal, rather than multiple journals, at a time."

Can anyone confirm the last sentence is true about not being allowed to submit N-Assay paper to multiple journals?