Vice Chancellor Joseph R. Slights III on Monday blocked a last-ditch effort by dissident stockholders to revive a Revlon challenge to OM Group Inc.’s $1 billion buyout by Apollo Global Management in 2015.

The plaintiffs, a group of pension funds and a New York-based investment firm, had argued that OM board members rushed to sell the company on the cheap in order to avoid a public proxy fight with an activist shareholder.