Chubb Ltd CB reported better than expected second-quarter earnings July 24 and declared quarterly dividend of 73 cents Aug. 9. It is payable on Oct. 12 to shareholders of record at the close on Sept. 21. Deutsche Bank's Joshua Shanker downgraded Chubb from Hold to Sell and decreased the price target from $135 to $126. In the wake of the Q2 print, Shanker said he concluded the market is misunderstanding several aspects of the insurance company. They are: Shanker doubts post-merger Chubb's ability to grow its business at the same rate as its peers. It's uncertain whether one-time items can deliver earning surprises.The analyst sees a trend of decline in net favorable prior-period development.Chubb is unlikely to maintain market peak underwriting margins.The consensus EPS forecast is too high and will be revised down as it has been in the past, the analyst said. SourceDownside potential still holds: stochastics head south. $CB, Chubb Limited / D