Theories of causation grounded in counterfactual dependence face the problem of profligate omissions: numerous irrelevant omissions count as causes of an outcome. A recent purported solution to this problem is proportionality, which selects one omission among many candidates as the cause of an outcome. This paper argues that proportionality cannot solve the problem of profligate omissions for two reasons. First: the determinate/determinable relationship that holds between properties like aqua and blue does not hold between negative properties like not aqua and (...) not blue. Negative properties are those at stake in omissive causation. Second: proportionality misconstrues the nature of the problem to be solved. (shrink)