The start-up is expected to focus on an emerging but fast-growing e-commerce market: providing expert advice and services through the Internet, sources speculated. As one surmised, Keen.com hopes to be a marketplace for advice and services just as eBay is for auctions.
Keen.com's Web site now reads simply: "Coming soon."
Jacob declined comment. A spokeswoman also refused to comment, except to say an announcement is planned for Monday concerning a "new company in the consumer Internet space."
Keen.com--as in sharp-witted or mentally acute--is based on an idea from a New York-based entrepreneur named Scott Faber. Under Faber, another name had been considered as well: Ether.com.
Benchmark is providing capital, sources said, and Jacob will be the company's chief executive. In stealth mode at this stage, Keen.com is operating largely out of Benchmark's Silicon Valley offices.
If it indeed is focusing on e-commerce services, Keen.com would face intense competition. A recently launched start-up called Advoco.com--marketed under the name Exp.com--also specializes in online expert advice. As Exp.com's Web site puts it: "We connect individuals seeking advice with expert advisors across a range of categories--from parenting to pets." The backers include CMGI.
Another competitor is Xpertsite.com, which boasts: "We connect people with questions to Xperts--real people with answers."
Keen.com will contend that it is superior because of proprietary technology and tools, sources said. Jacob's experience also is expected to provide a boost.
Jacob joined Benchmark as an entrepreneur in residence in July. He previously spent two years as a top executive at Microsoft after the software giant bought his company, Dimension X. Among the first Java start-ups, Dimension X was a software and professional services firm.
Benchmark's portfolio includes eBay, epinions, and 1-800-flowers, among others. It also was a major backer of Pointcast, which failed to go public and was sold instead.