In 2017, pharmacy benefits giant Express Scripts saw its net income skyrocket by 33% year-over-year to $4.51 billion. But a healthy chunk of that income—$1.38 billion—was attributable to the tax law signed by President Donald Trump late last year. While Scripts touted investments in its workforce as a result of the corporate tax cut, it also repurchased 45.9 million of its shares in a stock buyback of nearly $2.95 billion. In 2018, the company will be sure to keep an eye on potential pushback on benefits managers at large, which some critics say contribute to high drug prices because of the industry’s convoluted drug rebate structure. Express Scripts is also in the midst of a proposed $54 billion megadeal to be purchased by insurer Cigna.