The activist investors looking to shake up CNET (NSDQ: CNET) continue to accumulate their holdings, undeterred by the roadblocks put up by the company. Sandell Asset Management said in a filing that it had purchased another 800,000 shares at $9.06 each, bringing its total holdings to 3.47 million shares, or 2.3 percent of the company. When it last announced the level of its investment, it had 1.5 percent of the shares, plus a separate 3.5 percent non-voting economic interest. The largest investor of the crew, Jana, says in its latest filing that it owns 10.9 percent of the common shares, up from 10.5 percent as of its last update. It also has a non-voting economic interest, last reported at 6 percent. As of a week ago, the sum of the two firms’ voting and non-voting interests came to about 21.5 percent. With the latest accumulations, this level is nearing 23 percent.