Mergers and acquisitions are back in a big way this year, reaching their highest level since 2007.

The tally of the boom in deal-making is $1.7 trillion so far this year across more than 12,000 deals — the highest five-month run since before the crisis, when $2.4 trillion worth of deals were reported in 2007, according to Bloomberg data. Companies are also back to doing more jumbo deals: There have been 24 deals worth $10 billion or more so far this year. That’s almost twice as many as in the same time period a year ago and equal to the total number of deals in 2007, Bloomberg data show.

Multibillion-dollar deals in the communications and pharmaceutical industries have led the way, including Pfizer’s PFE  failed $117 billion bid for U.K. drug maker AstraZeneca and Comcast’s $45 billion takeover of Time Warner Cable. (Bloomberg tallies all bids proposed, including ones that are withdrawn or cancelled.)

Much of the deal-making activity is focused in Europe, where deals are up 114% year-over-year compared to a 70% boost in North America. Part of this is due to companies pushing for tax inversions, where the buyer will shift its own or the target company’s headquarters to benefit from a lower tax rate and save money.

Buyers looking to take advantage shifting tax burdens include deals such as Valeant’s VRX  $50 billion race for Allergan. The combined company would have a single-digit tax rate, Valeant CEO Michael Pearson said. A major savings, especially since Allergan’s 2013 tax rate was about 26%, according to Bloomberg data.

Other companies, such as Google, have continued to hold their global earnings abroad with the intention of buying foreign assets and avoid the taxes involved with re-shoring the funds to the U.S. Google told the Securities and Exchange Commission that it plans to use as much as $30 billion buying companies outside of the U.S. rather than bring the money back stateside, where it would face corporate taxes as high as 35%. General Electric is also using part of its $57 billion overseas cash horde to buy France-based Alstom’s energy business instead of bringing the money back into the U.S.

Companies were well positioned for the boom, which could continue through the rest of the year. After the financial crisis, businesses stockpiled cash to gird against more credit crunches, and the continually low interest rates supported by the Federal Reserve’s bond-buying program allow companies to supplement their stores with cheap funds.

Money has languished on their balance sheets, and, in some cases, activist investors have popped up to spur action. Not only are companies using their stockpiles to add to their roster, buybacks and dividends have also increased: Corporations put almost $600 billion towards share repurchases last year and authorized another $261 billion as of April this year, according to data from Birinyi Associates.

The benefit of all this buying and selling of businesses is less well-defined. Mohamed El-Erian, the former second-in-command at PIMCO, argued that the boom is benefiting primarily wealthy investors, leaving behind the rest of the economy. “On the surface, the deployment of cash should be good news for the real economy,” El-Erian wrote in a Bloomberg View column. “Unfortunately, the manner in which it has happened isn’t yet supportive enough for growth and jobs.”

El-Erian points out that many of these deals take advantage of “cost synergies” and savings, which boost stocks and benefit financial investors rather than the broader economy. Looking at one case this year, investors in Jos. A Banks and Men’s Warehouse, who ended their five-month back-and-forth bidding war at a nice $1.8 billion, gained about $1.7 billion simply due to the run-up in both stocks from prior to the first bid in October to when the deal was struck Mar. 11.

The real economy can gain if mergers result in investment in equipment, facilities and people, but “that is not yet the case for the majority of mergers,” El-Erian said.