A boutique bank just scored a huge payday on a $28 billion merger

Guggenheim Securities scored a monster payday Wednesday on the ACE Limited-Chubb merger, a $28 billion acquisition that creates an insurance industry behemoth.

Guggenheim is listed as the lone bank representing Chubb in the transaction. Morgan Stanley is on the other side of the deal. Both banks could potentially reap more than $100 million in deal fees, depending on how the transaction is structured.

Typically banks earn between 1% and 2% on big deals. But, a deal as huge as ACE's $28 billion buy sometimes command lower percentages. The stocks of both Chubb and ACE rose in trading Wednesday morning.

It comes in a year where boutique banks have continued to take more money from big investment banks. It also comes as M&A could potentially top all-time highs set in 2007.