Last year brought a shift in the financial fortunes of Houston-based litigation powerhouse Susman Godfrey. But the bigger shift may be in the firm's business model, which famously embraced high-stakes contingency matters and deemphasized hourly billing and fixed fees.

The firm's management recently made a strategic decision to stop expecting the majority of its revenue to come from contingency fees, according to founder and partner Steve Susman. It has also begun seeking to represent the types of oil and gas industry clients that might have once been the firm's adversaries, he said.

The moves come as net income at Susman Godfrey tumbled by 20 percent in 2016 from the previous year, which had been particularly profitable, Susman said.