This article documents the fact that ventures funded by two successful angel groups experience superior outcomes to rejected ventures: They have improved survival, exits, employment, patenting, Web traffic, and financing. We use strong discontinuities in angel- funding behavior over small changes in their collective interest levels to implement a regression discontinuity approach. We confirm the positive effects for venture operations, with qualitative support for a higher likelihood of successful exits. On the other hand, there is no difference in access to additional financing around the discontinuity. This might suggest that financing is not a central input of angel groups.

We build a tractable growth model in which multiproduct incumbents invest in internal innovations to improve their existing products, while new entrants and incumbents invest in external innovations to acquire new product lines. External and internal innovations generate heterogeneous innovation qualities, and firm size affects innovation incentives. We analyze how different types of innovation contribute to economic growth and the role of the firm size distribution. Our model aligns with many observed empirical regularities, and we quantify our framework with Census Bureau and patent data for US firms. Internal innovation scales moderately faster with firm size than external innovation.

The firm is almost entirely absent from models of immigration, and yet firms play a central role for high-skilled immigration. The H-1B visa program, for example, is a firm-sponsored entry where firms are responsible for every stage: from identifying the immigrant, to employing them, to filing for permanent residency on behalf of the immigrant. This central role of firms for high-skilled immigration suggests the traditional lens for evaluating the impact of immigration on natives through local area labor markets or national age-education approaches may miss important dynamics. We analyze the employment and wage trajectories of high-skilled workers born in America when a high-skilled immigrant arrives at their work site. We use linked employer-employee data during the 1995-2008 period from the Census Bureau for this exercise, which identifies the immigration status and country-of-birth of workers. We follow the subsequent career path of workers after high-skilled immigration occurs to the employee's work site both within firms (e.g., changes in employee salary, relocation to other sites) and across firms (e.g., movements to new jobs or out of workforce, long-term salary adjustments). The richness and depth of the Census Bureau data allow for multiple comparison points: selection on observables (e.g., age, tenure, salary levels and recent growth), varying immigration treatments across different work sites for the same firm for otherwise comparable employees, and (for a subset of cases and short time period at the end of our sample) randomization in H-1B admission lotteries.