What Harvard’s calendar may tell us about Facebook’s IPO.

Conventional wisdom is that Facebook will file for its IPO within the next few months. But, if so, someone should tell Sheryl Sandberg.

Sandberg is the social network’s chief operating officer, and its second-most powerful executive after mark Zuckerberg. She also was just announced as the keynote speaker at Harvard Business School’s Class Day, which takes place on may 23.

It would be highly unusual for Sandberg to give a public speech after her company has filed to go public, due to a variety of SEC-mandated quiet period restrictions. In theory, she could do so without mentioning anything about Facebook, but then why would HBS students want to hear from her? And we’re not just talking restrictions on material items like revenue growth or earnings. Even certain qualitative assessments could run afoul of the quiet period police.

Earlier this week, there was speculation about an imminent Facebook IPO filing due to some changes to the ways in which its stock is being traded on secondary markets. CNBC reporter Kayla Tausche threw cold water on the rumor, writing:

The company’s COO Sheryl Sandberg is scheduled to speak in Davos on Sunday, which makes it highly unlikely that Facebook will file before then.

Well, now we have Sandberg scheduled to speak on may 23. It’s certainly possible that Facebook will file beforehand, and that Sandberg and HBS will figure out a way to make it all work out. But since all of us are just scavenging for breadcrumbs here, this particular announcement seemed to be worth mentioning…

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