Silver Lake Sumeru - focuses on technology investments in middle-market companies.

Calera Capital is a private equity firm focused on investments in middle-market companies.

In New York, Chemical says it has relationships with 41 percent of the 10,000 middle-market companies, more than any other bank.

Chemical does business with about 20,000 middle-market companies, or 36 percent of the New York area market.

After the merger is completed, the bank will have business ties with more than half of the middle-market companies in the area.

The firm, focuses on companies facing operational or financial challenges, particularly middle-market companies.

The firm invests in middle-market companies within the media, communications and information-based sectors.

Its client base consists primarily of middle-market companies that spend from about $500,000 to $20 million a year on travel expenses.

Lincoln International is an independent investment bank specializing in advisory services and financings for middle-market companies.

The firm assists in the process of raising both equity and debt capital for middle-market companies.