Roche forced to extend Spark tender offer as investors sue over $4.3B merger

Roche’s $114.50-per-share offer for Spark Therapeutics represents a whopping 122% premium to the gene specialist’s closing price on the last trading day before the acquisition announcement. But some Spark investors still think the price is too low. So far, Spark investors have tendered only 29.4% of the shares outstanding, which doesn't exactly inspire confidence in the deal; Roche needs more than 50% to carry out the combo. The Swiss drugmaker said it's extending its tender offer to May 2 from the previous deadline of Wednesday. The lackluster results aren't Spark's only problem with its investors. The company faces shareholder lawsuits that call the deal price too low—a “bargain,” one suit claims—and question Spark's accounting methods and deal disclosures.