The most prolific startup acquirers of the past three years are Salesforce 1, OpenAI and Snowflake, according to Crunchbase data. These companies have acquired three or more seed- or venture-backed startups in the past 3 years. For Salesforce, this is nothing new for the company, which has purchased at least 91 companies in the last 20 years. However, for OpenAI, this has been followed by a shorter track record of M&A shopping spree. The most prolific M&As buyers also aren't always the biggest check-writers. For a broader picture view, we found six companies that made the biggest-ticket funded startup acquisitions of the last three years.