When Keith Rabois announced he was leaving Founders Fund to return to Khosla Ventures in January, it came as a shock to many in the venture capital ecosystem — and not just because Rabois is a big name in the industry.

It was surprising because unlike in many other fields, venture capitalists don’t traditionally move around very much — especially those that reach the partner or general partner level as Rabois had.

VC funds have 10-year life cycles and partners have good reason to stay that course. In some instances, they may be a “key man” on a firm’s fund, meaning that if they leave, the fund’s LPs have the right to pull their capital out if they choose. Many partners and GPs also have some of their own money invested in their firms’ funds, which gives them further reason to stick around.

So, while big-name investor moves in venture capital aren’t common, they seem to have become so in recent months. So far this year, there have been notable instances of investors returning to old firms, striking out on their own or taking a pause from investing entirely.

Just today, Vic Singh, one of the co-founders of Eniac Ventures, announced he was stepping down from the firm he helped launch in 2009 to launch his own.

Singh joins a growing list of VCs who have left firms recently.