No requirement to do conference calls
It's good practice to improve investor confidence, but there are a number of companies on the Big Board and Nasdaq that don't do calls. I do think companies that hold calls and frequently communicate are awarded higher valuations all else equal. I'm sure there's been research done on this topic, but I can't recall it off the top of my head.
What is required for disclosure? Any material event, but that's obviously subject to interpretation. Those events should be disclosed as soon as they are known. The company isn't supposed to wait for 10-Qs and 10-Ks to disclose their occurrence.
I do think using Twitter is good, but it's not enough. Investors need to hear the CEO explain what is going on AND have an opportunity for Q&A.
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