Research summary: We consider conditions in which incumbent firms are particularly poised to benefit from knowledge spilling in from new ventures that employ individuals previously employed by the focal incumbent firm. We distinguish between inventors who leave their incumbent employers to found spin‐outs and those who become non‐founding employees of existing new ventures. Using a sample of new ventures and incumbent firms in the U.S. information technology (IT) sector, we find that incumbents are more likely to benefit from patented knowledge that spills in from their spin‐outs than from new ventures that employ non‐founding inventors formerly employed by the respective incumbent. Any advantage that parent firms have in reaping such knowledge quickly dissipates, however, when these parents have a history of misappropriating the intellectual property of others. Managerial summary: It has long been acknowledged that new ventures can acquire valuable knowledge from their larger and more established counterparts by hiring away their talented employees. We consider the possibility of a reverse flow of knowledge where established firms learn from those new ventures that have poached employees from them. We find that established information technology (IT) firms are more likely to learn and build on the technology of their spin‐outs (i.e., new ventures founded by their former inventors) than from new ventures that simply employ non‐founding inventors formerly employed by the respective IT firm. Any advantage that these IT firms had in reaping technical know‐how from their spin‐outs quickly dissipated, however, when they had a history of misappropriating the intellectual property of others. Copyright © 2016 John Wiley & Sons, Ltd.