(Reuters) -Investment manager 40 North Management LLC said on Thursday it had sweetened its bid for W.R. Grace & Co to $4.63 billion, or $70 per share, from a previous offer of $65 per share of the chemical company. W.R. Grace had rejected previous unsolicited offers from 40 North, its top shareholder, as inadequate. The latest offer represents a premium of 16.9% to W.R. Grace’s last close. Shares of the company closed 2.2% higher at $61.19. Columbia, Maryland-based W.R. Grace said late on Thursday it would review the letter sent by 40 North in a timely manner and requested for additional customary information, including details of the company’s debt and equity financing commitments.