 Swiss drug giant Roche Holding AG OTC: RHHBY announced a big-ticket acquisition that would boost its presence in the diagnostics market, setting the tempo for a merger Monday. What Happened: Roche said it has entered into a definitive agreement to acquire GenMark Diagnostics NASDAQ: GNMK for 24.05 per share in cash, or about 1.8 billion, on a fully diluted basis. 