Yahoo! Mail
Yahoo! made a deal with the online communications company Four11 for co-branded white pages. Marvin Gavin, who worked at Four11 as the Director of International Business Development, said "We always had a bias about being acquired by Yahoo. They were more entrepreneurial than Microsoft. We had a great cultural fit – it made a lot of sense." In the end, Yahoo! acquired Four11 for $96 million. The purpose behind acquiring Four11 was the company's RocketMail webmail service, which launched in 1997. Yahoo! announced the acquisition on October 8, 1997, close to the time that Yahoo! Mail was launched. Yahoo! chose acquisition rather than internal platform development, because, as Healy said, "Hotmail was growing at thousands and thousands users per week. We did an analysis. For us to build, it would have taken four to six months, and by then, so many users would have taken an email account. The speed of the market was critical."
EGroups
The service was started by Scott Hassan in 1997 as an email list archiving service called FindMail (mimicking the name "FindLaw", a company co-founded by Martin Roscheisen). Carl V. Page, Jr. joined the company in May 1997. When Martin Roscheisen joined as CEO in March 1998, FindMail was incorporated (in June 1998) and shifted its focus towards hosting email groups. FindMail, then renamed "eGroups", quickly grew to 250,000 users before taking a venture finance round of $810,000 from Atlas Venture in May 1998. In October 1998, with 1.2 million users (growing at 12,000 users per day), Excite offered to acquire the company for $40m but the company decided instead to take $5.1 million more investment money from Sequoia Capital. 
In Sept 1999, eGroups started work on an initial public offering but instead merged with ONElist, with 13 million users exchanging more than 1.3 billion email messages each month. In January 2000, the company raised a further $42 million and filed a S1 with the SEC on March 23, 2000.