Deal for Clay County Savings Bank leaves Verimore Bank primed to add market share in a fast-growing Kansas City neighborhood

Columbus-based Northwest Bancshares finalized its acquisition of Penns Woods Bancorp; Barclays becomes the second U.K.-based bank to leave the Zero Banking Alliance; BankUnited announces the appointment of Michael Mitchell as executive vice president, director of branch banking; and more in this week's banking news roundup.

The largest bank in Missouri, which completed the acquisition of Heartland Financial USA early this year, is on track to switch Heartland's systems over to UMB's systems in mid-October. The conversion should help realize "the next big slug" of expense savings, UMB's CFO said.

Investor reaction to the proposed $8.6 billion deal has been sour, with both banks' share prices falling more than 11% as of Friday afternoon. The response appeared to reflect the market's distaste for mergers of equals and the risks associated with crossing the $100 billion-asset threshold.

The Dallas-based bank is the subject of a scathing new report by HoldCo Asset Management, which says it should take advantage of current market conditions to sell itself. The investment firm accused Comerica's management of making poor decisions and failing to address its lagging stock price.

The two Southeast banks agreed to combine in a transaction valued at $8.6 billion. Synovus CEO Kevin Blair would be chief executive of the combined bank, but a slim majority of board members would come from Pinnacle.

"During my tenure as CEO, we have never entertained discussions regarding the sale of the company with any financial institution," CEO Michael O'Grady told analysts Wednesday. The Wall Street Journal reported last month that the two banks' CEOs had at least one conversation about a potential merger.

The credit card giant must reckon with the high costs of integration before it can start reaping the benefits from its landmark acquisition. CEO Richard Fairbank said Tuesday that those costs will exceed the company's original $2.8 billion guidance.

The Columbus, Georgia-based bank is working with a financial adviser and has recently held merger talks with at least one rival, people familiar with the matter said.

The Evansville, Indiana-based bank has hired Tim Burke to oversee commercial and community banking, along with wealth, credit and marketing.