From the summary of The Committee Markup Process in the House of Representatives (RL30244, Dec. 10, 2018):
Committees do not actually change the texts of the bills they mark up. Instead, committees vote on amendments that their members want to recommend that the House adopt when it considers the bill on the floor. The committee concludes a markup not by voting on the bill as a whole, but by voting on a motion to order the bill reported to the House with whatever amendments the committee has approved. A majority of the committee must be present when this final vote occurs. For all other stages of markups, committees may set their own quorum requirements, so long as that quorum is at least one-third of the committee’s membership.