Activist investor Carl Icahn said on Wednesday that he was forging ahead with his proxy battle with Motorola even after the mobile phone maker gave into his demands to split up the company.

Investor Carl Icahn said Monday he is suing Motorola Inc to force it to hand over documents related to its mobile devices business, and he urged investors to elect his slate of candidates to the Motorola board.

Billionaire investor Carl Icahn has raised his stake in U.S. cell phone maker Motorola to 6.3 percent from 5 percent, according to a regulatory filing on Wednesday.

Biogen Idec said after markets closed Wednesday that it ended its review of strategic options after failing to receive any definitive takeover bids.

Motorola, which has been fending off criticism from shareholder Carl Icahn, has named Greg Brown as its chief executive, replacing Ed Zander, who will remain chairman until the company's annual meeting in May.

Business software maker BEA Systems said it would provide confidential information to shareholder Carl Icahn explaining why it rejected a $17-per-share takeover bid from Oracle.

Two years after it successfully fought off the efforts of Carl Icahn and the plan authored by Lazard Frères to break apart Time Warner, the company seems ready to embrace it, CNBC's David Faber reports.