Group work is frequently part of idea generation, despite evidence that group interaction may reduce productivity during brainstorming sessions. Idea quantity is one aspect of creativity, but the originality of ideas generated is also important. In this paper, we examine how different aspects of group interaction, such as who makes the most contributions to an idea and the number of group members contribute to an idea, impact the originality of concepts generated by engineering students. We found that the most original concepts were produced when the concept originator was the top contributor to the design, and when the majority of group members contributed to the concept, particularly among senior students. These results are discussed in relation to previous work and suggestions are made for future research that assesses the interaction between design fixation and group processes.