Jim Spanfeller, the CEO of Forbes.com and the man largely credited with turning the magazine's website into dominant source for financial news on the web, is stepping down at the end of the summer.

Jeff Bercovici of Daily Finance reports:

Spanfeller did not respond to messages, but his departure is thought by insiders to be a result of pressure by Elevation Partners, the private equity group that bought a large minority stake in Forbes three years ago. In May of this year, Elevation co-founder Roger McNamee resigned from the Forbes board and was replaced by Bret Pearlman, another Elevation Partners executive whose arrival was seen to herald a round of cost-cutting. Since then, rumors have circulated that Spanfeller's days were numbered, even though he is said to be favored by president/COO Tim Forbes.

Forbes CEO Steve Forbes announced the news in a memo to company employees tonight. In it he said:

Jim has done a monumental job of bringing Forbes.com to the lead position in business websites, and secured Forbes.com as the must visit site for not only global business leaders but also anyone interested in the finest business reporting and analysis available. At present Forbes.com has 18 million unique visitors a month.

Along the way, Jim has overseen the development and growth of Forbes Digital, which includes Forbes.com, ForbesTraveler.com, Investopedia.com, RealClearPolitics.com, RealClearMarkets.com, Real Clear Sports, and Forbes Business and Finance Blog Network, which together reach 40 million unique visitors a month.

This immense growth on the digital side of the business was spearheaded, pursed, and led by Jim with enormous success. The digital world is still uncharted with few rules, and Jim's intellect, creativity, and business acumen helped bring us our number one position. For this the Forbes family is very grateful and we wish him all the success in his future plans.

Nothing further is known at this time about who will replace Spanfeller or what his future plans are.

Sources Say Forbes.com CEO Stepping Down [Jeff Bercovici/Daily Finance]
Forbes CEO Jim Sapnfeller Out: Here's the Internal Memo [Peter Kafka/All Things D]