Activist investor Blue Harbour's Clifton Robbins on Monday escalated his campaign at Investors Bancorp (ISBC) - Get Report , arguing that the de-mutualized bank could become an acquisition candidate in the not-to-distant future.

"We'd like to see significant share [buyback] increase and we'd like to see increasing dividends, and we think they will be the beneficiary from tax relief and regulatory reform," Robbins told the Sohn 2017 investor conference. "if that happens that'd be a good thing. We would support them if they find accretive M&A to do. And at some time... at the right price we think the company is an attractive acquisition candidate."

Robbins first discussed the fund's Investors Bancorp investment in May 2015 at the Las Vegas hedge fund conference SALT. At the time he argued that it would pay regular dividends and produce large share buybacks in the coming years. Robbins praised Investors Bancorp's management at both conferences. "We know them we like them we trust them, they have a lot of equity in the business," Robbins said at Sohn.

Robbins argued that he expects Investors Bancorp's shares to spike upwards to as much as $17, $18 or $19 a share, up from its recent share price of $13.60 a share. The bank's share price is up from about $12 a share in May 2015, when Robbins first discussed the investment. 

Robbins and his team generally don't engage in proxy fights, lawsuits or public criticism of the companies in which they invest-an approach that sets the fund apart from the majority of activist investors. Instead, Blue Harbour takes a collaborative approach, making private suggestions and working behind-the-scenes with boards and management over a number of years to effect change. If the company doesn't respond to the firm's suggestions, Blue Harbour won't make an investment-or it will sell its stake.

Robbins has been at it for a while: his fund, formed in 2004, is based in Greenwich, Conn.

 He noted that Investors Bancorp has about $1 billion of excess capital. Investors Bancorp de-mutualized about three years ago, from a mutual holding company structure to a stock ownership company. For Robbins that shift indicates that M&A maybe part of its future.

"Some 68% of those banks that convert to full-stock ownership are acquired within five years. Three years have gone by," Robbins said. "This is an attractive asset."

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