There's a lot been said about the biotech bubble, but with a robust M&A market helping generate new growth opportunities for pharma companies, we're not ready to call it a bubble just yet.

Parts of the pharma space has been a real head-scratcher of late.

Teva Pharmaceuticals'(NYSE: TEVA) pursuit of Mylan (NYSE: MYL) was brought to an abrupt end last week when Teva agreed to buy up the generic drug business of Allergan (NYSE: AGN).

This ends a long game of cat and mouse between Teva and Mylan. With that, Mylan shares are down more than 15% over the last week.

As part of its defense, Mylan launched a bid for Perrigo Company (NYSE: PRGO). We'll soon see whether Mylan was serious about buying Perrigo.

However, it's not all rosy in the pharma space.

One of the largest biotechs around, Biogen (NASDAQ: BIIB), with a $75 billion market cap, has lost 22% of its market value in the last 30 days.

That doesn't mean biotech isn't worth owning. Big pharma is one of the great places to play the boom in mergers and acquisitions. And there's likely more to come as many of the industry's largest players look to stave off slowing growth.

Here are the industry's three kingmakers and where they'll likely go hunting for new deals:

Pharma Kingmaker No. 1: Biogen

The recent troubles with Biogen could mean that it gets active in the merger and acquisition market. Granted, Biogen hasn't had troubles in the conventional sense, but more a slowdown in growth. It recently lowered its revenue and earnings guidance for the rest of this year.

With that, Biogen is likely on the hunt to buy a company that can have an immediate impact to the top and bottom lines.

The other beauty of Biogen is that it has the balance sheet to get a relatively large deal done, carrying less than $600 million in debt. One prime target could be Vertex Pharmaceuticals (NASDAQ: VRTX), which recently got FDA approval to for a medicine to treat the most common form of cystic fibrosis.