After graduation he worked for Claris, a subsidiary of Apple Computer, developing software for the Macintosh. In 1991, he co-founded Ink Development Corp. with three friends. The company included an Internet shopping segment and was later renamed eShop Inc. Omidyar worked as a software engineer for eShop until the end of 1994, when he became a developer services engineer for General Magic, a mobile communication platform company. In 1996, eShop was sold to Microsoft, but Omidyar remained fascinated by the technical challenges of online commerce.
While living and working in the San Francisco Bay Area, he met and married Pamela Wesley, a graduate student in biology who later embarked on a career as a management consultant. In a much repeated story, Omidyar originally created an online auction site to help his wife trade and collect Pez candy dispensers, but in his interview with the Academy of Achievement, Omidyar derides the story as "media-enhanced." Other eBay spokesmen have since described it as a publicist's fabrication. In fact, Omidyar was already intrigued by the technical problem of establishing an online venue for direct person-to-person auction of collectible items. He created a simple prototype on his personal web page, and launched an online service called Auction Web as a sole proprietorship on Labor Day weekend in 1995. The first item sold on the site was not a Pez dispenser, but a broken laser pointer. Omidyar was astonished that anyone would pay for the device in its broken state, but the buyer assured him he was deliberately collecting broken laser pointers. Similar surprises followed. The business exploded as correspondents began to register trade goods of an unimaginable variety.
Pierre Omidyar changed the company's name to eBay in 1997 and began to advertise the service aggressively. He has served as Chairman of the Board since its incorporation. At first, he also served as Chief Financial Officer, President and CEO, but he relinquished these positions one by one, the last when he hired former Hasbro executive Meg Whitman to serve as CEO in 1998. At the time, eBay had barely 30 employees, half a million users and U.S. revenues of $47 million. By the time eBay went public that fall, the site had more than a million registered users. The share price nearly tripled on the first day of trading and Omidyar's holdings made him a billionaire overnight.
In 2002, eBay acquired the online payment processing firm PayPal, which it uses to process most of its online transactions, compelling many online sellers to employ the service. At the same time, eBay diversified its services, allowing sellers to engage in fixed-price and "best offer" sales as well as conventional auctions. Software developers can create applications to integrate into the site through the eBay Developers Program. In 2005, eBay opened a category for buying and selling surplus industrial machinery and business equipment. Many large companies now use eBay to set prices for their products and services.
Pierre Omidyar serves on the Board of Trustees of Tufts University, The Santa Fe Institute and The Omidyar Foundation. In November 2005, Pierre and Pamela Omidyar announced their gift of $100 million to endow the Omidyar-Tufts Microfinance Fund. At the time, it was the largest gift in the history of Tufts University, as well as the largest private allocation of capital to microfinance by any individual or family. The fund, administered by the Board of Trustees of Tufts University, invests in international microfinance initiatives designed to empower people in developing countries to lift themselves out of poverty. Ten years after going public, eBay had expanded around the world, employing more than 15,000 persons to serve a customer base numbering in the hundreds of millions, operating in 30 countries, with especially large presences in China and India. In 2009, eBay reported revenues of $8.727 billion, and Forbes magazine estimated Omidyar's net worth at $3.6 billion.