We incorporate a stylized version of the DOE in the model and compare
equilibrium outcomes with and without the doctrine. Under the DOE, the
inventor simply claims E and has the right to exclude the competitor from
making and using any embodiment in E or F; thus, the doctrine allows the
inventor to avoid literally claiming F and incurring the cost of refinement. In
contrast, in the version of the model without the DOE, the inventor must pay
refinement costs and literally claim F to get protection over the embodiments in
The model demonstrates the social costs and benefits of the DOE. When
refinement costs are high, social value arises from the DOE because it provides
an important incentive to inventors, and because it promotes efficient invest-
ment in refinement. When refinement costs are low, the DOE offers neither of
these benefits, and thus should be curtailed to increase certainty and decrease
rent-seeking.