Document ownership attributions often have direct consequences for evaluation, in both classrooms and workplaces. But when writers work collaboratively, ownership attributions are not straightforward. This study, about how and why collaborative writers make such attributions, reports that interviewed workplace writers emphasized product criteria (quality and liability), while surveyed student writers emphasized process criteria (teamwork and workload). A review of previous research suggests that such a difference may result from cultural differences between the academy and the workplace. That analysis further suggests how both instructors and practitioners could help newcomers make successful transitions to professional writing, by foregrounding ownership attitudes.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>