3191
But it took federal authorities who regulate medical devices four months to acknowledge only one of the alleged defects , and for the company , St. Jude Medical , to patch it .
 ( discover vulnerability: acknowledge,  medical devices: vulnerable system, federal authorities: discoverer, one of the alleged defects: vulnerability) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: phishing, data breach, ransom, discover vulnerability, patch vulnerability, Arguments type: vulnerable system, capabilities, vulnerability, number of victim, issues addressed, compromised data, damage amount, common vulnerabilities and exposures, victim, patch number, number of data, tool, discoverer, time, purpose, place, payment method, releaser, vulnerable system version, attacker, supported platform, patch, price, vulnerable system owner, trusted entity, attack pattern. 
Text: {0} 
Answer:
 ( discover vulnerability: acknowledge,  medical devices: vulnerable system, federal authorities: discoverer, one of the alleged defects: vulnerability) 