Earlier this year, T-Mobile and Sprint announced that they would merge. If approved, their combination would shrink the number of major wireless carriers in the United States from four to three. Now, 14 different organizations have penned a letter to Democratic House leaders requesting a hearing on the proposed merger.

The letter, which is signed by leaders of groups like the Open Markets Institute and Public Knowledge, was addressed to two of the most influential Democratic House lawmakers, Reps. Jerry Nadler (D-NY) and Frank Pallone (D-NJ). Once the new Congress kicks off in January, both lawmakers will be chairing committees with oversight jurisdiction on the potential merger deals.

“Announcing hearings to examine the single largest pending wireless telecommunications merger, and one of the largest in the nation’s history, would be an excellent first step to implementing your vision for stronger antitrust enforcement, protecting consumers, promoting competition, and standing up for American workers,” the groups wrote.

The Senate Judiciary Committee held a hearing in June with both T-Mobile’s CEO John Legere and Sprint’s executive chairman Marcelo Claure, but there have been no similar hearings in the House.