reduces the incentives to exert effort in R&D activities. Then, drawing on the signaling role of patents highlighted by the …

In Spence's (1973) signaling by education model and in many of its extensions, firms can only infer workers …' productivities. We characterize the trade-offs between signaling by workers and costly information acquisition by firms. Information … workers have low productivity. Our analysis applies also to other signaling problems, e.g. the financial structure of firms …