Relx, the UK-listed information and analytics group, is buying California-based academic publisher Bepress — its third acquisition in the San Francisco Bay area in the past 18 months. Although Relx did not disclose the amount its science and health business Elsevier had paid for the company, which was founded in 1999 by three academics at the University of California, Berkeley, one person briefed on the deal valued the transaction at £100m.