Big Fish Games founder Paul Thelen has assumed the roles of president and CEO, effective today. He previously held those positions, but handed them over to Jeremy Lewis while Thelen (pictured) served as chief strategy officer and chairman of its board of directors. Lewis will continue on Big Fish’s board of directors.

Under Lewis’s guidance the company has grown to be one of the largest casual game companies, and recently reported its ninth straight year of record revenues after seeing its sales increased by 30 percent year-over-year to $180 million in 2011. Working together, Lewis said, “We’ve grown the company organically through several life stages and emerged as a leading digital brand with strong momentum and huge continued potential.”

Big Fish is nearing the commercial launch of its Universal Cloud Gaming Service platform, the expansion of its free-to-play games business, and furthering its Facebook game presence with Card Ace: Casino, Thelen said.

AllThingsD is among the observers who have been expecting Big Fish to seek an Initial Public Offering since October, when it distributed sizable dividend checks to its shareholders and the majority of its employees.

Big Fish was founded in 2002. The Seattle-based company is best known for its catalog of more than 2,500 games, including hits like Mahjong Towers and the Mystery Case Files series, on multiple platforms in more than 150 countries and with customer support in ten languages. The company is headquartered in Seattle, with regional offices in Luxembourg; Vancouver; Cork, Ireland; and Oakland, Calif.

Related links:

Big Fish Games – official site

Big Fish Games – press release

Gamasutra – Big Fish’s former president, CEO returns to head the company

AllThingsD – Big Fish Games Founder Paul Thelen Takes Back Reins From CEO (Memo)

VentureBeat – Big Fish Games CEO hands reins back to founder Paul Thelen