OTTAWA (AP) ¿ Corel Corp., the maker of WordPerfect and other software, said Thursday its largest shareholder has increased the price at which it wants to buy the company. Corel said investment company Vector Capital, which owns 68 percent of Corel through Corel Holdings LP, initially offered to buy the company for $3.50 per share, or $30 million. But on Wednesday night, it bumped up its offer by 50 cents, to $4 per share, according to a filing with the Securities and Exchange Commission. Corel's board said it is evaluating the revised offer. In March 2008, Vector Capital offered to buy the company for $11 per share. But it withdrew the offer five months later after the company said it would pursue alternative relationships. In August 2008, Corel got a buyout offer from two parties for $12.50 per share, pending their due diligence. The offer was later cut to $10.50 per share and withdrawn in October 2008 as banks tightened credit due to the financial crisis. Vector Capital got back into the picture in August 2009 and two months later made an offer to buy the rest of Corel it doesn't already own for $3.50 per share. Corel also develops and sells WinZip, Paint Shop image editing software and other products. Shares of Corel, based in Ottawa, Ontario, were up 36 cents, or 9.9 percent, to $4.01 in afternoon Nasdaq trading.