Larry Fink, chairman and CEO of BlackRock, recently sent another one of his famous letters. Building on previous promises to value all stakeholders, this year’s message to CEOs outlines BlackRock’s new role as a responsible champion of the environment — it vows to both safeguard people’s money and promote a “sustainable and inclusive capitalism.”

The world’s largest asset management company says that beginning this year it will divest from thermal coal and “mak[e] sustainability integral to portfolio construction and risk management.” Fink insists that in the future BlackRock “will be increasingly disposed to vote against management and board directors when companies are not making sufficient progress on sustainability-related disclosures and the business practices and plans underlying them.”

But on closer examination, the details of BlackRock’s plan are less exciting. The company’s vow to pull back from thermal coal refers to its actively managed portfolios. Roughly three-quarters of the company’s portfolios are passively managed, their assets automatically selected to track the global marketplace. (BlackRock’s strong growth over the past decade owes almost entirely to investment flowing into its exchange-traded funds and other types of passive investing.) The vast majority of BlackRock’s more than $17 billion investment in coal sits in passively invested portfolios.