UPDATE via The Harvard Crimson:

"Roughly 20 students remained in Massachusetts Hall, home to the office of University President Drew G. Faust, late Thursday night after a group of more than 30 stormed and occupied the building that morning."
 

Harvard student activists occupied the offices of President Drew Faust Thursday morning, demanding that the university sell its investments in fossil fuel companies.
Jasmine Opie is a junior from Scituate and a leader of Divest Harvard. She says 34 students are participating in the sit-in, and they won't say how long they plan to stay. According to reports, the students are outfitted with water, food, and diapers.

Opie says the group wants Harvard to divest from the top 200 fossil fuel companies.

According to Opie: "The actual mechanics of divestment are definitely sticky because fossil fuels are at this point ubiquitous to our economy. Divestment is not a tactic about economically damaging the fossil fuel companies directly when you sell your stocks... But rather it's about creating political will that sways away from fossil fuel companies and toward renewable by stigmatizing the fossil fuel industry."

Opie says Faust has agreed to meet with protesters. But The Harvard Crimson reports that the condition for meeting was that the students cease their occupation.

While 19 colleges and universities across the nation have adopted divestment policies, Faust has steadfastly refused. 

Faust's position is that Harvard's $36-billion endowment is not a political tool.