Analysts say the Federal Reserve has embarked on a fourth round of quantitative easing that poses a hazard to equity markets — but the central bank denies it.

Federal Reserve Chairman Jerome Powell, speaking at an October news conference, was adamant that the central bank’s intervention in the overnight U.S. repurchase-agreement (repo) market — as well as the buying of up to $60 billion in Treasury bills each month — does not amount to another round of QE. But critics say it’s a distinction without a difference.