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Great Deal! AbbVie Will Buy Shire and Investors Will Be Rewarded

Tickers in this article: ABBV ALSMY COV GE MDT SHPG

NEW YORK (TheStreet) -- Nothing gets investors riled up like mergers and acquisitions. A great deal can present a company that has tons of cash with instant access to growth, allowing it to conquer new markets that would have otherwise take years to achieve.

Although AbbVie's $51.5 billion offer (upped from $46.5 billion) for drug maker Shire has been rebuffed on multiple occasions, investors should not get discouraged.

AbbVie, which saw an almost 9% jump in its stock price when the rumors of the deal first emerged two weeks ago, has given back almost all of those gains. With Thursday's close of $55.79, shares are still up almost 6% year to date.

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These deals take time. Medtronic's $43 billion deal for Covidien was rumored for almost a year before both companies realized they needed each other. The most recent example is General Electric's on-again/off-again dance with Alstom .

Negotiating tactics aside, what I think is most important to remember are the accretive benefits for the acquiring companies. In the case of AbbVie, there are plenty, which should boost the stock towards the $70 level in the next 12 months.

According to Mark Percell, analyst at Barclays, a deal for Shire could yield close to 20% in accretive earnings for AbbVie in the next six years --and that's not even factoring AbbVie's already strong drug business being anchored by its blockbuster arthritis drug Humira.

Humira accounted for close to 60% of AbbVie's total revenue in 2013. AbbVie's management understands that it can't live on Humira indefinitely. This is where Shire comes in.

Shire would make AbbVie immediately more diversified. I believe Shire's ability to unlock incremental value to be the main reason why AbbVie recently upped its offer by 10%.